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Sample records for masseter muscle pain

  1. Antero-posterior activity changes in the superficial masseter muscle after exposure to experimental pain.

    Science.gov (United States)

    Türp, Jens C; Schindler, Hans J; Pritsch, Maria; Rong, Qiguo

    2002-04-01

    The aim of this randomized, controlled, double-blind study was to examine how the activation pattern of the masseter muscle changes during natural function when experimental pain is induced in a discrete anterior area of the muscle. In 20 subjects, three bipolar surface electrodes and three intramuscular fine-wire electrodes (antero-posterior mapping) were simultaneously attached above and in the right masseter muscle to record the electromyographic (EMG) activity during unilateral chewing before and after infusion of a 0.9% isotonic and 5% hypertonic saline bolus in the anterior area of the muscle. The activity of the contralateral masseter muscle was registered by surface electrodes. In addition, the development of pain intensity was quantitatively measured with a numerical rating scale (NRS). While both saline concentrations caused pain, the hypertonic solution evoked stronger pain. The experiments also provided evidence of a significant although differential activity reduction of the ipsilateral masseter muscle in the antero-posterior direction. The activity reduction decreased with increasing distance from the location of the infusion. The results support the idea that the strategy of differential activation protects the injured muscle while simultaneously maintaining optimal function.

  2. Entropy as a new measure of mechanical pain sensitivity in the masseter muscle

    DEFF Research Database (Denmark)

    Castrillon, Eduardo; Sato, Hitoshi; Tanosoto, Tomohiro

    barely painful” and “100” defined as “most pain imaginable”. All subjects participated in 3 sessions in a randomized order with injections of glutamate (0.5 ml, 1 mol/L), lidocaine (0.5 ml, 1%) or isotonic saline (0.5 ml, 0.9%)into the mid-portion (X = 2, Y = 3) of the masseter muscle. All sessions...... and 2 kg stimulation (Plidocaine and placebo......ENTROPY AS A NEW MEASURE OF MECHANICAL PAIN SENSITIVITY IN THE MASSETER MUSCLE Author Block: E. E. Castrillon1, H. Sato2,3, T. Tanosoto4, T. Arima4, L. Baad-Hansen1, P. Svensson1, 1Clinical Oral Physiology, Århus Univ., Aarhus, Denmark, 2Dept. of Dentistry & Oral Physiology, Sch. of Med., Keio Univ...

  3. Electromyographic biofeedback training for reducing muscle pain and tension on masseter and temporal muscles: A pilot study.

    Science.gov (United States)

    Criado, Laura; de La Fuente, Antonio; Heredia, Margarita; Montero, Javier; Albaladejo, Alberto; Criado, José-María

    2016-12-01

    Due to the absence of agreement about an effective unified treatment for temporomandibular disorders, non-invasive therapies such as EMG-biofeedback generate a greater interest. Furthermore, most studies to the present show methodological deficiencies that must be solved in the future, which makes important to emphasize this line of studies. Fourteen patients were selected for this case series study, and replied to a questionnaire concerning awareness of bruxism, painful muscles, and muscle tension. They also practiced an intraoral exploration (occlusal analysis and mandibular dynamics), and an extraoral exploration of the head and neck muscles and the temporomandibular joint. Before each session, patients responded to a questionnaire about the subjective perceived improvement. In each session, a period of three minutes of pre-biofeedback EMG activity of right masseter and temporal muscles was registered, then patients performed 30 iterations of visual EMG-biofeedback training and finally, a period of three minutes of post-EMG activity was also registered for those muscles. Patients performed four sessions. A decrease in painful symptoms was found for all patients since the first session. EMG activity decreases (pmuscles during the biofeedback training stage, in the four sessions. It is also observed a decrease (pmuscle at the post-biofeedback stage, in the second and third sessions. There is likewise a decrease in EMG post-biofeedback activity of the temporal muscle (pmuscles during the session. This decrease persists during the post-biofeedback period since the second session. Also there is a decrease in painful symptoms for all patients. Key words:Muscle tension, muscle pain, EMG-biofeedback, masseter muscle, temporal muscle.

  4. A Case of Painful Hemimasticatory Spasm with Masseter Muscle Hypertrophy Responsive to Botulinum Toxin

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    Jin-Hyuck Kim

    2009-10-01

    Full Text Available Hemimasticatory spasm (HMS is a rare disorder of the trigeminal nerve characterized by paroxysmal involuntary contractions of the unilateral jaw-closing muscles. HMS has been frequently described in association with facial hemiatrophy or localized scleroderma. A 42-year-old female presented with involuntary paroxysmal spasms of the left face, of 6 months duration. Her lower face on the left was markedly hypertrophied without skin lesions. An electrophysiological study indicated that the masseter reflexes and masseteric silent period were attenuated on the affected side. Surface electromyography demonstrated irregular bursts of motor unit potentials at high frequencies up to 200 Hz. Magnetic resonance imaging of the head showed marked hypertrophy of the left masseter muscle. Biopsy of the hypertrophied masseter muscle was normal. Repeated local injections of botulinum toxin noticeably reduced the size of the hypertrophied muscle as well as improved the patient’s symptoms.

  5. Effect of experimental jaw-muscle pain on the spatial distribution of surface EMG activity of the human masseter muscle during tooth clenching.

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    Castroflorio, T; Falla, D; Wang, K; Svensson, P; Farina, D

    2012-02-01

    This study tested the hypothesis that painful injections of glutamate into the human masseter muscle differentially affect the distribution of the electromyographic (EMG) activity in the masseter muscle at rest and during tooth clenching. Surface EMG signals were recorded bilaterally from the superficial masseter of nine healthy men with a grid of 32 electrodes, before and after intramuscular injection of glutamate or isotonic saline, during rest and isometric contractions at 20%, 40%, 60% and 80% of the maximal voluntary bite force. Intramuscular injection of glutamate evoked moderate pain (0-10 visual analogue scale: 6·4 ± 1·4), with sensory-discriminative characteristics of the perceived pain, evaluated with the use of the McGill Pain Questionnaire (MPQ), similar to those previously reported for patients with temporomandibular disorders. There was no effect of the glutamate injection on EMG amplitude during rest, whereas during tooth clenching, the spatial distribution of the masseter EMG activity on both sides was more uniform in the painful condition compared to the control condition. Moreover, the overall EMG amplitude decreased on both sides during the more forceful tooth clenching following glutamate injection. In conclusion, a unilateral painful stimulation was associated with a bilateral inhibition of the masseter muscles during tooth clenching which resulted in a more uniform distribution of EMG activity. © 2011 Blackwell Publishing Ltd.

  6. Pain and intramuscular release of algesic substances in the masseter muscle after experimental tooth-clenching exercises in healthy subjects.

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    Dawson, Andreas; Ghafouri, Bijar; Gerdle, Björn; List, Thomas; Svensson, Peter; Ernberg, Malin

    2013-01-01

    To investigate whether experimental tooth clenching leads to a release of algesic substances in the masseter muscle. Thirty healthy subjects (16 females, 14 males) participated. During two sessions, separated by at least 1 week, intramuscular microdialysis was performed to collect masseter muscle 5-hydroxytryptamine (5-HT) and glutamate as well as the metabolic markers pyruvate and lactate. Two hours after the start of microdialysis, participants were randomized to a 20-min repetitive experimental tooth-clenching task (50% of maximal voluntary contraction) or a control session (no clenching). Pain and fatigue were measured throughout. The Friedman and Wilcoxon tests were used for statistical analyses. No alterations were observed in the concentrations of 5-HT, glutamate, pyruvate, and lactate over time in the clenching or control session, or between sessions at various time points. Pain (P pain and fatigue developed with this experimental tooth-clenching model, but they were not associated with an altered release of 5-HT, glutamate, lactate, or pyruvate. More research is required to elucidate the peripheral release of algesic substances in response to tooth clenching.

  7. Changes following denervation to the masseter muscle

    Institute of Scientific and Technical Information of China (English)

    Lei Zhang

    2008-01-01

    BACKGROUND: Masseter muscle nerve is often injured in mandible osteotomy. What changes in food intake and masseter muscle will be brought after masseter muscle nerve injury?OBJECTIVE: This study was designed to selectively establish animal models of denervated masseter muscle and investigate the effects of severing masseter muscular nerve on masseter muscle and animal's food intake. DESIGN, TIME AND SETTING: A randomized controlled animal experiment was performed at the Laboratory Animal Center, Nanfang Hospital, Southern Medical University from September to November 2005. MATERIALS: A total of 50 healthy, adult, SPF-grade, New Zealand rabbits, of both genders, were used to develop an animal model of selectively denervated masseter muscle.METHODS: Five rabbits were randomly selected as normal controls. According to various mutilation methods, the remaining animals were randomly divided into 3 experimental groups, with 15 rabbits in each group: masseter muscular neural stem denervated, masseter muscular neural superior branch-denervated, and masseter muscular neural inferior branch-denervated groups. Self-control comparison was performed on each animal. The right masseter muscle served as the experimental side, and the left masseter muscle served as the control side. In each group, 3 time points (2, 8, and 24 weeks post-surgery) were allotted for observation. MAIN OUTCOME MEASURES: At the pre-set time points, masseter muscular thickness was measured with a Logic 500 color Doppler ultrasonic diagnostic apparatus. Masseter muscle tissue was resected for hematoxylin eosin staining. Masseter muscular fiber diameter and area were measured with an optical microscope. Masseter muscle tissue was sectioned and nicotinamide adenine dinucleotide tetrazolium oxidoreductase (NADH-TR) and adenosine triphosphatase staining were performed. Following staining, the sections were quantitatively analyzed using an IBAS200 image analyzer.RESULTS: Post-surgery food intake: No abnormal

  8. Long lasting pain hypersensitivity following ligation of the tendon of the masseter muscle in rats: A model of myogenic orofacial pain

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    Dubner Ronald

    2010-07-01

    Full Text Available Abstract Background A major subgroup of patients with temporomandibular joint (TMJ disorders have masticatory muscle hypersensitivity. To study myofacial temporomandibular pain, a number of preclinical models have been developed to induce myogenic pain of the masseter muscle, one of the four muscles involved in mastication. The currently used models, however, generate pain that decreases over time and only lasts from hours to weeks and hence are not suitable for studying chronicity of the myogenic pain in TMJ disorders. Here we report a model of constant myogenic orofacial pain that lasts for months. Results The model involves unilateral ligation of the tendon of the anterior superficial part of the rat masseter muscle (TASM. The ligation of the TASM was achieved with two chromic gut (4.0 ligatures via an intraoral approach. Nocifensive behavior of the rat was assessed by probing the skin site above the TASM with a series of von Frey filaments. The response frequencies were determined and an EF50 value, defined as the von Frey filament force that produces a 50% response frequency, was derived and used as a measure of mechanical sensitivity. Following TASM ligation, the EF50 of the injured side was significantly reduced and maintained throughout the 8-week observation period, suggesting the presence of mechanical hyperalgesia/allodynia. In sham-operated rats, the EF50 of the injured side was transiently reduced for about a week, likely due to injury produced by the surgery. Somatotopically relevant Fos protein expression was indentified in the subnucleus caudalis of the spinal trigeminal sensory complex. In the same region, persistent upregulation of NMDA receptor NR1 phosphorylation and protein expression and increased expression of glial markers glial fibrillary acidic protein (astroglia and CD11b (microglia were found. Morphine (0.4-8 mg/kg, s.c. and duloxetine (0.4-20 mg/kg, i.p., a selective serotonin-norepinephrine reuptake inhibitor

  9. Esterase profile of human masseter muscle

    DEFF Research Database (Denmark)

    Kirkeby, S; Moe, D; Vilmann, H

    1988-01-01

    The esterase profile of fresh human masseter muscle was investigated by use of histochemistry and electrophoresis. The histochemical methods included reactions for alpha-naphthyl esterase, myofibrillar ATPase, reverse myofibrillar ATPase and succinic dehydrogenase. In frozen sections of the muscl...

  10. An animal model for human masseter muscle: histochemical characterization of mouse, rat, rabbit, cat, dog, pig, and cow masseter muscle

    DEFF Research Database (Denmark)

    Tuxen, A; Kirkeby, S

    1990-01-01

    .4, type IM fibers react moderately, and type II fibers react strongly. Rat and mouse masseter muscles contained type II fibers only, as did some rabbit masseter muscles, whereas other rabbit masseter muscles possessed equal amounts of type I and II fibers. Cat and dog masseter muscles possessed both type...

  11. Inhibitory reflex responses of masseter muscle in anterior open bite

    OpenAIRE

    Priyada, SANTILAKANAWONG; Hiroaki, KIRIMOTO; Yoichiro, SEKI; Kunimichi, SOMA; Orthodontic Science, Department of Orofacial Development and Function, Division of Oral Health Sciences, Graduate School, Tokyo Medical and Dental University

    2003-01-01

    Animal studies indicated that loss of occlusal contact between maxillary and mandibular teeth causes altered functional activity of periodontal mechanoreceptors. The alteration of periodontal mechanoreceptors may influence jawmuscle reflex and masticatory muscle activity. In this study, the inhibitory reflex response of masseter muscle in subjects with anterior open bite was investigated. The study population included 10 subjects with anterior open bite with no muscle pain or craniomandibular...

  12. No effect of experimental occlusal interferences on pressure pain thresholds of the masseter and temporalis muscles in healthy women

    NARCIS (Netherlands)

    Michelotti, A; Farella, M; Steenks, MH; Gallo, LM; Palla, S

    It has been suggested that occlusal interferences may lead to pain and tenderness of the masticatory muscles. Tender jaw muscles are more sensitive to pressure pain, as assessed by means of pressure algometry. We tested the effects of occlusal interferences on the pressure pain threshold of the jaw

  13. Masseter and medial pterygoid muscle hypertrophy.

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    Guruprasad, R; Rishi, Sudhirkumar; Nair, Preeti P; Thomas, Shaji

    2011-09-26

    Hypertrophy refers to an enlargement caused by an increase in the size but not in the number of cells. Generalised masticatory muscle hypertrophy may affect the temporalis muscle, masseters and medial pterygoids in a variety of combinations. Masseteric hypertrophy may present as either unilateral or bilateral painless swelling of unknown origin in the region of angle of mandible. It is a relatively rare condition and presents a diagnostic dilemma. While the history and clinical examination are important in differentiating this benign condition from parotid or dental pathology, they cannot necessarily exclude rare malignant lesion within the muscle. Advanced imaging modalities like CT and MRI are essential to confirm the diagnosis. Here the authors are reporting a unique case of masseter muscle hypertrophy along with medial pterygoid hypertrophy which was missed clinically but confirmed using CT and MRI.

  14. Pressure pain thresholds assessed over temporalis, masseter, and frontalis muscles in healthy individuals, patients with tension-type headache, and those with migraine--a systematic review.

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    Andersen, Sanne; Petersen, Marie Weinreich; Svendsen, Anette Sand; Gazerani, Parisa

    2015-08-01

    A systematic review was conducted to identify and summarize the available scientific literature addressing pressure pain threshold (PPT) values over the temporalis, masseter, and frontalis muscles in healthy humans, patients with tension-type headache (TTH), and those with migraine both in males and females. Six relevant medical databases for the literature search were included: PubMed, Web of Science, Cochrane, CINAHL, BioMed Central, and Embase. The search strategy was performed applying 15 keywords (eg, pressure pain threshold, temporalis muscle, tension type headache, pressure algometer) and their combinations. A total of 156 articles were identified, and 40 relevant articles were included. The main outcomes of the systematic review were extracted, and it was demonstrated that the PPT values in general were lower in patients compared with healthy subjects, and this was especially noted for temporalis in both females (migraine: 231.2 ± 38.3 kPa craniofacial muscles of healthy subjects, patients with TTH, and those with migraine to provide the PPT value ranges. Based on these findings, a set of guidelines was established to assist future studies including PPT assessments over craniofacial muscles.

  15. Masseter and medial pterygoid muscle hypertrophy

    OpenAIRE

    R, Guruprasad; Rishi, Sudhirkumar; Nair, Preeti P; Thomas, Shaji

    2011-01-01

    Hypertrophy refers to an enlargement caused by an increase in the size but not in the number of cells. Generalised masticatory muscle hypertrophy may affect the temporalis muscle, masseters and medial pterygoids in a variety of combinations. Masseteric hypertrophy may present as either unilateral or bilateral painless swelling of unknown origin in the region of angle of mandible. It is a relatively rare condition and presents a diagnostic dilemma. While the history and clinical examination ar...

  16. Bimaxillary protrusion with masseter muscle hypertrophy treated with titanium screw anchorage and masseter surgical reduction.

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    Hashimoto, Takashi; Kuroda, Shingo; Kamioka, Hiroshi; Mishima, Katsuaki; Sugahara, Toshio; Takano-Yamamoto, Teruko

    2009-04-01

    This case report describes the treatment of a patient with bimaxillary protrusion and masseter muscle hypertrophy. At age 21 years 7 months, this woman had temporomandibular disorder (TMD) symptoms, severe bimaxillary protrusion, and a prominent mandibular angle with facial asymmetry. After an attempt to alleviate the TMD symptoms with occlusal splint stabilization, portions of the masseter muscle and the mandible were surgically removed. Titanium screws were placed bilaterally in both arches, and a retraction force was applied. After active treatment for 38 months, the convexity of the facial profile with lip protrusion was improved remarkably, and good occlusion was achieved. The prominent mandibular angle with facial asymmetry was improved as a result of the surgical reduction of the masseter muscle and the modeling ostectomy near the masseteric tuberosity. The TMD symptoms disappeared, and the jaw movement pattern became normal. Therefore, our results suggest that this combination treatment would be useful for masseter muscle hypertrophy for morphologic and functional problems.

  17. Hipertrofia benigna do músculo masseter Benign masseter muscle hypertrophy

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    Daniel Zeni Rispoli

    2008-10-01

    Full Text Available A hipertrofia idiopática do músculo masseter (HIM é uma patologia pouco freqüente e de causa desconhecida. Alguns autores correlacionam tal condição com hábitos de mascar gomas, disfunção da articulação temporomandibular (ATM, hipertrofias congênitas e funcionais, e distúrbios emocionais (nervosismo e ansiedade. A maioria dos pacientes queixa-se da alteração estética decorrente da assimetria facial, também chamada "face quadrada", no entanto, sintomas como trismo, protrusão e bruxismo também podem ocorrer. Os objetivos deste estudo foram: relatar um caso de HIM e descrever a sintomatologia e o tratamento realizado. O paciente relatava aumento bilateral na região do ângulo da mandíbula de evolução lenta e progressiva. Negava dor ou desconforto, porém se queixava de otalgia bilateral, trismo noturno e ansiedade. Ao exame físico, observou-se hipertrofia bilateral de masseter sem alterações inflamatórias no local. Foi indicado tratamento cirúrgico com abordagem extra-oral. Exames complementares são indicados na dúvida diagnóstica. A conduta terapêutica varia de conservadora a cirúrgica, sendo que esta depende principalmente da experiência e da habilidade do cirurgião.Idiopathic hypertrophy of the masseter muscle is a rare disorder of unknown cause. Some authors associate it with the habit of chewing gum, temporo-mandibular joint disorder, congenital and functional hypertrophies, and emotional disorders (stress and nervousness. Most patients complain of the cosmetic change caused by facial asymmetry, also called square face, however, symptoms such as trismus, protrusion and bruxism may also occur. The goals of the present investigation were: to report a case of idiopathic masseter hypertrophy, describe its symptoms and treatment. The patient reported bilateral bulging in the region of the mandible angle, of slow and progressive evolution. He did not complain of pain or discomfort, however there was bilateral

  18. Functional Compartmentalization of the Human Superficial Masseter Muscle

    OpenAIRE

    Guzmán-Venegas, Rodrigo A.; Biotti Picand, Jorge L.; Francisco J Berral de la Rosa

    2015-01-01

    Some muscles have demonstrated a differential recruitment of their motor units in relation to their location and the nature of the motor task performed; this involves functional compartmentalization. There is little evidence that demonstrates the presence of a compartmentalization of the superficial masseter muscle during biting. The aim of this study was to describe the topographic distribution of the activity of the superficial masseter (SM) muscle's motor units using high-density surface e...

  19. Bilateral masseter and internal pterygoid muscle hypertrophy: a diagnostic challenge.

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    Andreadis, Dimitrios; Stylianou, Florentia; Link-Tsatsouli, Iris; Markopoulos, Anastasios

    2014-01-01

    To describe an unusual case of bilateral masseter and pterygoid muscle hypertrophy. A 53-year-old female patient presented with a bilateral, painless swelling at the parotid areas without improvement after using antibiotics/systemic corticosteroids/nonsteroidal anti-inflammatory agents. Her medical history included thyroid nodules, but no dental/occlusal disorders were observed. The initial differential diagnosis included salivary gland/jaw bone/masseter pathology, but the CT/MRI revealed only an increase in the size of the masseter and pterygoid muscles. The patient was informed of the benign nature of the swelling and was advised to discontinue the use of nonsteroidal anti-inflammatory agents. The bilateral hypertrophy of masseter muscles should be considered in differential diagnosis in cases of unilateral or bilateral swelling of the parotid or lateral mandible area. © 2013 S. Karger AG, Basel.

  20. Efficacy of massage treatment technique in masseter muscle hardness: robotic experimental approach.

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    Hiraiwa, Yuichiro; Ariji, Yoshiko; Kise, Yoshitaka; Sakuma, Shigemitsu; Kurita, Kenichi; Ariji, Eiichiro

    2013-10-01

    The study aimed to clarify the masseter muscle hardness in patients with myofascial pain, to examine their changes after massage, and to analyze whether the hardness can be an index for massage treatment. Sixteen patients with myofascial pain (12 with unilateral and 4 with bilateral masseter muscle pain) and 24 healthy volunteers were enrolled in this study. The masseter hardness between patients and the healthy volunteers was compared. The changes in the hardness in patients after massage were examined. The relation of the hardness with massage regimens and efficacies was analyzed. There was a significant right-and-left difference of the hardness in patients, although there was no difference in the healthy volunteers. The hardness decreased after massage. The pretreatment asymmetry index of the hardness showed a significant correlation with the massage pressure. It was concluded that there was a significant difference between the right and left masseter hardness in patients with myofascial pain. After massage treatment, the masseter hardness and right-and-left difference decreased. The hardness may be an index for determining the massage pressure.

  1. Modulation of an inhibitory reflex in single motor units in human masseter by tonic painful stimulation.

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    Svensson, P; McMillan, A S; Graven-Nielsen, T; Wang, K; Arendt-Nielsen, L

    1999-12-01

    Perioral electrical stimuli cause inhibitory reflex responses in single motor-units (SMU) and surface electromyographic (EMG) recordings from voluntary contracted human jaw-closing muscles. Tonic experimental masseter pain has recently been shown to reduce the inhibitory reflex response in surface EMG recordings but the effect on SMU activity has not been described. In this study, motor-unit action potentials were recorded with wire electrodes inserted into the left masseter in eleven subjects. The subjects kept the SMU firing rate around 10 Hz by feedback. Ninety-nine electrical stimuli were applied sequentially to the left mental nerve with increasing stimulus delays in steps of 1 ms after the preceding motor unit action potential. The inhibitory reflex in SMU was recorded before, during and after infusion of hypertonic saline (5%) into the ipsilateral masseter muscle. Spike train data were used to calculate (1) the mean pre- and post-stimulus inter-spike-intervals (ISI) in all of the 99 trials, (2) cumulative changes in firing probability, and (3) estimation of the compound inhibitory post-synaptic potential (IPSP) in the masseter motoneuron. Tonic masseter pain did not change pre-stimulus SMU firing characteristics but the mean ISI for the first post-stimulus discharge (158.2+/-9.2 ms) was significantly decreased compared to the pre-pain (175.8+/-11.3 ms, Pmasseter pain compared to pre-pain and post-pain conditions. In conclusion, this study indicates that tonic masseter pain has a net excitatory effect on the inhibitory jaw-reflexes, which could be mediated by presynaptic mechanisms on the involved motoneurons.

  2. Peripheral primitive neuroectodermal tumor in masseter muscle.

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    Yazc, Haşmet; Yiğit, Barş; Doğan, Sedat; Sunter, Ahmet Volkan; Behzatoğlu, Kemal

    2013-05-01

    Primitive neuroectodermal tumor is a member of malignant small round cell tumors. These tumors especially originate from the central and autonomous nervous system. However, these tumors may be originated from peripheral tissues and are called peripheral primitive neuroectodermal tumor. A 14-year-old girl attended to the Ear Nose Throat Clinic with the complaint of progressive painless swelling mass for 2 months on the right side of the face. Neck magnetic resonance imaging showed 3.5 × 2.5 × 2-cm isointense mass on T1 and hyperintense on T2 sequences. There was no pathological lymphadenopathy on computed tomographic scan. As a result of mandibular cortical invasion seen on computed tomographic scan, radical surgical excision was decided as surgical treatment. Total parotidectomy with preserving facial nerve and partial mandibulectomy with a 2-cm margin of safety were done, and reconstruction plaque applied to the mandible. Two lymph nodes were seen at the submandibular region. For this reason, prophylactic supraomohyoid neck dissection had also been performed. Pathological assessment proved the diagnosis of PNET, and chemoradiotherapy was planned for the patient.To our knowledge, this is the second reported case in literature. In this present case, peripheral neuroectodermal tumor in the masseter muscle and its diagnosis and treatment process were reported with literature review.

  3. Masseter thickness, endurance and exercise-induced pain in subjects with different vertical craniofacial morphology.

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    Farella, Mauro; Bakke, Merete; Michelotti, Ambra; Rapuano, Alessia; Martina, Roberto

    2003-06-01

    The aim of the study was to compare neuromuscular features of the masseter muscle in subjects with different vertical craniofacial morphology. Fifteen short-faced (mandibular plane-Frankfurt plane angle or = 23 degrees) male students participated. The thickness of the masseter was assessed by ultrasonography. Onset and endurance of exercise pain were recorded during sustained biting at a level of 15% of maximum voluntary contraction and 30 micro V electromyographic activity. Pain and fatigue was measured on visual analog scales before and after the biting, as well as before and after 10 min chewing. Statistical comparison showed that the masseter muscle was significantly thicker (+15%) in the short-faced than the normal- to long-faced subjects. The pain onset time and endurance time were also consistently shorter in short-faced subjects, whereas the intensity of pain and fatigue did not differ significantly between the two groups. Multiple stepwise regression showed positive influence from the mandibular plane inclination and the masseter thickness on the pain onset time and endurance time. The present findings support the concept that subjects with different craniofacial morphology show neuromuscular differences.

  4. MOTOR UNIT TERRITORIES AND FIBER TYPES IN RABBIT MASSETER MUSCLE

    NARCIS (Netherlands)

    WEIJS, WA; JUCH, PJW; KWA, SHS; KORFAGE, JAM

    1993-01-01

    The myosin heavy chain (MHC) content and spatial distribution of the fibers of 11 motor units (MUs) of the rabbit masseter muscle were determined. The fibers of single MUs were visualized in whole-muscle serial sections by a negative periodic acid/Schiff reaction for glycogen after they had been dep

  5. Dimensions and geometry of the temporomandibular joint and masseter muscles.

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    Zurowski, R; Gosek, M; Aleksandrowicz, R

    1976-01-01

    The bio-engineering team presents its suggestion of a method for the measurement of the temporomandibular joint and masseter muscles in order to determine the parameters necessary for exact sciences and indispensable for unified and objective cognitive studies. Ten formalin-fixed human cadavers served for the studies. The preparations were prepared by the modified method of anatomical procedure. Linear and angular measurements of temporomandibular joint and masseter muscles were carried out with the use of the three-dimensional Cartesian system of OXYZ coordinates in relation to frontal, sagittal and horizontal planes. The physiological cross-sections of the masseter, temporal, lateral and medial pterygoid muscles were also determined. The collected data make it possible to develop a mathematical three-dimensioned model of the osseo-articulo-muscular system of the mastication organ.

  6. THE CAPILLARY PATTERN IN HUMAN MASSETER MUSCLE DURING AGEING

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    Erika Cvetko

    2013-10-01

    Full Text Available The effect of ageing on the capillary network in skeletal muscles has produced conflicting results in both, human and animals studies. Some of the inconsistencies are due to non-comparable and biased methods that were applied on thin transversal sections, especially in muscles with complicated morphological structures, such as in human masseter muscle. We present a new immunohistochemical method for staining capillaries and muscle fibres in 100 µm thick sections as well as novel approach to 3D visualization of capillaries and muscle fibres. Applying confocal microscopy and virtual 3D stereological grids, or tracing capillaries in virtual reality, length of capillaries within a muscle volume or length of capillaries adjacent to muscle fibre per fibre length, fibre surface or fibre volume were evaluated in masseter muscle of young and old subjects by an unbiased approach. Our findings show that anatomic capillarity is well maintained in masseter muscle in old subjects; however, vascular remodelling occurs with age, which could be a response to changed muscle function and age-related muscle fibre type transformations.

  7. Relationship between masseter muscle size and maxillary morphology.

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    Uchida, Yasuki; Motoyoshi, Mitsuru; Shigeeda, Toru; Shinohara, Akihiko; Igarashi, Yu; Sakaguchi, Masahito; Shimizu, Noriyoshi

    2011-12-01

    The aim of this study was to investigate the relationship between masseter muscle size and craniofacial morphology, focusing on the maxilla. Twenty-four patients (11 males and 13 females; mean age 27.6 ± 5.6 years) underwent cephalometric analyses. Ultrasonography was used to measure the cross-sectional area (CSA) of the masseter muscle and bite force was measured using pressure sensitive film. The results showed that CSA-relaxed was positively correlated with upper anterior face height (UAFH)/total anterior face height (TAFH) and negatively with lower anterior face height (LAFH)/TAFH and LAFH (P < 0.05). CSA-clenched was correlated positively with SN-palatal, FH-palatal, UAFH/TAFH, and lower posterior face height (LPFH)/total posterior face height (TPFH) and negatively with LAFH/TAFH, LAFH, upper posterior face height (UPFH)/TPFH, and UPFH (P < 0.05). Bite force was positively correlated with LPFH/TPFH and negatively with UPFH/TPFH (P < 0.05). As the masseter became larger, the anterior maxillary region tended to shift downwards relative to the cranial base, whereas the posterior region tended to shift upwards. The decrease in LAFH/TAFH and increase in LPFH/TPFH as the size of the masseter muscle increases may be influenced not only by the inclination of the mandibular plane but also by the clockwise rotation of the maxilla.

  8. Acoustic myography, electromyography and bite force in the masseter muscle.

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    Tortopidis, D; Lyons, M F; Baxendale, R H

    1998-12-01

    Acoustic myography (AMG) offers some advantages over electromyography (EMG) in certain circumstances, but the use of AMG on the jaw-closing muscles has not been fully tested. The purpose of this study was to examine the relationship between AMG, EMG and force in the masseter muscles of nine healthy male subjects. The AMG was recorded using a piezoelectric crystal microphone and the EMG was recorded simultaneously with surface electrodes. Force was recorded between the anterior teeth with a strain-gauge transducer. Analysis showed that Pearson's correlation coefficient was 0.913 for force/AMG and 0.973 for force/EMG in all subjects, indicating a linear relationship between force, AMG and EMG at the four different force levels tested (25-75% of maximum). It is apparent that AMG may be used as an accurate monitor of masseter muscle force production, although some care is required in the technique.

  9. Ultrasound measurements of the masseter muscle as predictors of cephalometric indices in orthodontics: a pilot study.

    Science.gov (United States)

    Naser-Ud-Din, S; Sampson, W J; Dreyer, C W; Thoirs, K

    2010-09-01

    This study investigated the potential of ultrasound measurements of the masseter muscle to accurately predict indices normally derived from cephalograms. Masseter muscle measurements on 11 adults (22 to 30 y) were made using lateral cephalometrics and extended field-of-view ultrasound. The ultrasound technique was validated in a simulation pilot study using 12 dry skulls and raw chicken breasts. Twenty cephalometric variables were analyzed against four ultrasound measurements of the masseter muscle. Highly significant correlations (r = 0.81-0.85, p = 0.001-0.002) between ultrasound measurements of the masseter muscle and cephalometric measurements representing the length of the superficial masseter muscle, the length and shape of the mandible and vertical facial proportions were demonstrated. Predictive equations from regression analyses were constructed to deduce ramus length and shape from the ultrasound measurements. The results provide pilot data suggesting that ultrasound is a potential clinical tool for sequential evaluation of masseter muscle length in orthodontics and facial muscle growth studies.

  10. Fatigue in the masseter and temporalis muscles at constant load.

    Science.gov (United States)

    Sforza, Chiarella; Zanotti, Gianfranco; Mantovani, Enrica; Ferrario, Virgilio F

    2007-01-01

    Fatigue is usually defined as the point at which a particular level of force can be no longer maintained. In the present study, surface EMG of the masseter and temporalis anterior muscles was measured in ten healthy young adults performing a unilateral molar (right side) clench. The subjects clenched on a bite force transducer at a fixed force level of 13 kg (127 N) as long as they could (endurance). The test ended when the subjects could no longer produce the required bite force. From the EMG recordings, the median power frequency was calculated at the beginning of the task (T0), after one minute of clenching (T1), and at the end of the task (T2, endurance time). For each subject and muscle, percentage decrements in the median power frequency were also computed at T1 and T2. Endurance time ranged between 79 and 470 s. Significant modifications in the median power frequency in both masseter muscles (right side, p=0.003; left side, p=0.02, analysis of variance) were found, with a significant difference for the median frequency at T2 (p0.05). Additionally, at T1, significant percentage decrements in the median power frequency were found for both right side muscles (p0.05) were not significant. A significant effect of side was found (p=0.007, analysis of variance), without effects of muscle and no muscle x side interaction. At T2, both masseter muscles and the right side temporalis had a significant modification in their median power frequency. Overall, the modifications were larger in the masseter than in the temporalis muscles (p=0.022, analysis of variance), without effects of side and no muscle x side interaction. In conclusion, a fixed submaximal muscular contraction provoked fatigue modifications in the EMG power spectra that were well comparable to those obtained in previous investigations using forces computed as percentages of individually assessed maximum bite forces The present protocol (endurance clenching at a fixed force level) could be used as both a

  11. Muscle pain

    African Journals Online (AJOL)

    Causes of muscle pain include stress, physical activity, infections, hyper or .... Acupuncture. It is a traditional Chinese-based therapeutic method which ..... and Spinal Mechanisms of Pain and Dry Needling Mediated Analgesia: A Clinical.

  12. Jaw-opening accuracy is not affected by masseter muscle vibration in healthy men.

    Science.gov (United States)

    Wiesinger, B; Häggman-Henrikson, B; Wänman, A; Lindkvist, M; Hellström, F

    2014-11-01

    There is a functional integration between the jaw and neck regions with head extension-flexion movements during jaw-opening/closing tasks. We recently reported that trigeminal nociceptive input by injection of hypertonic saline into the masseter muscle altered this integrated jaw-neck function during jaw-opening/closing tasks. Thus, in jaw-opening to a predefined position, the head-neck component increased during pain. Previous studies have indicated that muscle spindle stimulation by vibration of the masseter muscle may influence jaw movement amplitudes, but the possible effect on the integrated jaw-neck function is unknown. The aim of this study was to investigate the effect of masseter muscle vibration on jaw-head movements during a continuous jaw-opening/closing task to a target position. Sixteen healthy men performed two trials without vibration (Control) and two trials with bilateral masseter muscle vibration (Vibration). Movements of the mandible and the head were registered with a wireless three-dimensional optoelectronic recording system. Differences in jaw-opening and head movement amplitudes between Control and Vibration, as well as achievement of the predefined jaw-opening target position, were analysed with Wilcoxon's matched pairs test. No significant group effects from vibration were found for jaw or head movement amplitudes, or in the achievement of the target jaw-opening position. A covariation between the jaw and head movement amplitudes was observed. The results imply a high stability for the jaw motor system in a target jaw-opening task and that this task was achieved with the head-neck and jaw working as an integrated system.

  13. Ultrasonographic assessment of the swelling of the human masseter muscle after static and dynamic activity

    DEFF Research Database (Denmark)

    Bakke, M; Thomsen, C E; Vilmann, A

    1996-01-01

    Work-related fatigue, pain and disorders in skeletal muscles have been related to prolonged static and dynamic activity. Such contractions have been shown to impair blood flow and increase muscle thickness and fluid. In the present study the effect of static and dynamic activity was evaluated from...... changes in masseter thickness as a measure of oedema, simultaneously with assessment of perceived pain/discomfort and cardiovascular responses. As static activity, fourteen young healthy women bit at 15% maximal voluntary contraction on bite-force transducers in the molar regions until exhaustion or 20.......5%) than dynamic activity (4.3%), whereas heart rate rose significantly only during dynamic exercise (13.3%). Hence, activity was associated with muscular swelling and pain, and, despite the relatively small size of the masticatory muscles, also with general cardiovascular responses....

  14. Prolonging the duration of masseter muscle reduction by adjusting the masticatory movements after the treatment of masseter muscle hypertrophy with botulinum toxin type a injection.

    Science.gov (United States)

    Wei, Jiao; Xu, Hua; Dong, Jiasheng; Li, Qingfeng; Dai, Chuanchang

    2015-01-01

    Botulinum toxin type A (BTX-A) is widely used for the clinical treatment of masseteric hypertrophy. Until now, few reports have discussed how to prolong the duration of its effectiveness. This study evaluated that purposely adjusting the masticatory movements is possible of postponing the masseter muscle rehypertrophy. Ninety-eight patients were randomly and equally divided into 2 groups, and 35 U BTX-A per side was injected into the masseters. The thickness and volume of the masticatory muscles were measured by ultrasound and computerized tomography, respectively. Patients in Group 1 were instructed to strengthen their masticatory effort during the denervated atrophic stage of the masseter (the interval was evaluated by real-time ultrasound monitoring), whereas patients in Group 2 were not given this instruction. When the masseter muscle began to recover, patients in both groups were instructed to reduce their chewing. The duration of the masseter muscle rehypertrophy was significantly prolonged in Group 1 patients. The thickness and the volume of the other masticatory muscles were significantly increased in Group 1 but were either slightly decreased or insignificantly different in Group 2. Purposely strengthening masticatory muscle movement during the denervated atrophic stage of the masseter can prolong the duration of masseter rehypertrophy.

  15. Functional compartmentalization of the human superficial masseter muscle.

    Directory of Open Access Journals (Sweden)

    Rodrigo A Guzmán-Venegas

    Full Text Available Some muscles have demonstrated a differential recruitment of their motor units in relation to their location and the nature of the motor task performed; this involves functional compartmentalization. There is little evidence that demonstrates the presence of a compartmentalization of the superficial masseter muscle during biting. The aim of this study was to describe the topographic distribution of the activity of the superficial masseter (SM muscle's motor units using high-density surface electromyography (EMGs at different bite force levels. Twenty healthy natural dentate participants (men: 4; women: 16; age 20±2 years; mass: 60±12 kg, height: 163±7 cm were selected from 316 volunteers and included in this study. Using a gnathodynamometer, bites from 20 to 100% maximum voluntary bite force (MVBF were randomly requested. Using a two-dimensional grid (four columns, six electrodes located on the dominant SM, EMGs in the anterior, middle-anterior, middle-posterior and posterior portions were simultaneously recorded. In bite ranges from 20 to 60% MVBF, the EMG activity was higher in the anterior than in the posterior portion (p-value = 0.001.The center of mass of the EMG activity was displaced towards the posterior part when bite force increased (p-value = 0.001. The topographic distribution of EMGs was more homogeneous at high levels of MVBF (p-value = 0.001. The results of this study show that the superficial masseter is organized into three functional compartments: an anterior, a middle and a posterior compartment. However, this compartmentalization is only seen at low levels of bite force (20-60% MVBF.

  16. Functional compartmentalization of the human superficial masseter muscle.

    Science.gov (United States)

    Guzmán-Venegas, Rodrigo A; Biotti Picand, Jorge L; de la Rosa, Francisco J Berral

    2015-01-01

    Some muscles have demonstrated a differential recruitment of their motor units in relation to their location and the nature of the motor task performed; this involves functional compartmentalization. There is little evidence that demonstrates the presence of a compartmentalization of the superficial masseter muscle during biting. The aim of this study was to describe the topographic distribution of the activity of the superficial masseter (SM) muscle's motor units using high-density surface electromyography (EMGs) at different bite force levels. Twenty healthy natural dentate participants (men: 4; women: 16; age 20±2 years; mass: 60±12 kg, height: 163±7 cm) were selected from 316 volunteers and included in this study. Using a gnathodynamometer, bites from 20 to 100% maximum voluntary bite force (MVBF) were randomly requested. Using a two-dimensional grid (four columns, six electrodes) located on the dominant SM, EMGs in the anterior, middle-anterior, middle-posterior and posterior portions were simultaneously recorded. In bite ranges from 20 to 60% MVBF, the EMG activity was higher in the anterior than in the posterior portion (p-value = 0.001).The center of mass of the EMG activity was displaced towards the posterior part when bite force increased (p-value = 0.001). The topographic distribution of EMGs was more homogeneous at high levels of MVBF (p-value = 0.001). The results of this study show that the superficial masseter is organized into three functional compartments: an anterior, a middle and a posterior compartment. However, this compartmentalization is only seen at low levels of bite force (20-60% MVBF).

  17. Masseter muscle rigidity: Atypical malignant hyperthermia presentation or isolated event?

    Directory of Open Access Journals (Sweden)

    Onyeka Tonia

    2010-01-01

    Full Text Available This report describes a case of masseter muscle rigidity encountered at the start of an elective gynaecological procedure. At preoperative assessment, the patient, a 41-year old woman with a previous non-eventful surgical and anesthetic history was given a Mallampati score of 3. Following suxamethonium administration, full mouth opening proved difficult. Laryngoscopy and tracheal intubation were not possible leading to the eventual use of a laryngeal mask airway and resulting in a successful anaesthetic outcome. A number of possibilities that may account for this situation as well as viable options for airway access in such cases are discussed below.

  18. Schedule-induced masseter EMG in facial pain subjects vs. no-pain controls.

    Science.gov (United States)

    Gramling, S E; Grayson, R L; Sullivan, T N; Schwartz, S

    1997-02-01

    Empirical reports suggest that oral habits (e.g., teeth clenching) may be behavioral mediators linking stress to muscle hyperreactivity and the development of facial pain. Another report suggests that excessive behavioral adjuncts develop in conjunction with fixed-time stimulus presentation. The present study assessed the extent to which the oral habits exhibited by facial pain patients are schedule-induced. Subjects with Temporomandibular Disorder (TMD) symptomatology (n = 15) and pain-free controls (n = 15) participated in a 4-phase experiment (adaptation, baseline, task, recovery) designed to elicit schedule-induced behaviors. Self-report of oral habits and negative affect were recorded after each phase. Objective measures of oral habits were obtained via behavioral observation and masseter EMG recordings. Results revealed that negative arousal significantly increased during the fixed-time (FT) task and was also associated with increased oral habits among the TMD subjects. Moreover, 40% of the TMD subjects and none of the controls exhibited a pattern of EMG elevations in the early part of the inter-stimulus interval that met a strict criteria for scheduled-induced behavior per se. Taken together, these results suggest that the TMD subjects were engaging in schedule-induced oral habits. The adjunctive behavior literature seems to provide a plausible explanation as to how oral habits develop and are maintained in TMD patients, despite their painful consequences.

  19. Haemodynamic changes in human masseter and temporalis muscles induced by different levels of isometric contraction.

    Science.gov (United States)

    Kim, Y J; Kuboki, T; Tsukiyama, Y; Koyano, K; Clark, G T

    1999-08-01

    This study evaluated the influence of low contraction forces on intramuscular haemodynamics in human masseter and temporalis using near-infrared tissue spectroscopy. This method allowed the intramuscular haemoglobin (Hb) to be assessed dynamically before, during and after a 5, 15, 25 and 100% maximum voluntary contraction (MVC). Twenty volunteers, 10 males and 10 females, without pain or dysfunction in the masticatory system were included in this study. Data were recorded for 30 s before, 30 s during and 5 min after the four sustained contraction tasks. The results showed that all four levels of voluntary contraction produced a clear haemodynamic response (during and after contraction) in both muscles. For analytical purposes, the maximum Hb achieved after 100% MVC was set equal to 1.00. In the masseter the mean peak Hb during the 5, 15, 25 and 100% MVC was 0.49, 0.92, 1.30 and 1.73 while after the contractions it was 0.50, 0.65, 0.78 and 1.00, respectively. In the temporalis the peak Hb during the contractions was 0.23, 0.36, 0.48 and 0.66 and after the contractions 0.32, 0.45, 0.56 and 1.00, respectively. Repeated-measures analysis of variance revealed a significant main effect for the different contraction levels both in the masseter (during contraction, p = 0.001; after contraction, parchitecture between the two muscles contributes to these differences in blood flow.

  20. Effects on craniofacial growth and development of unilateral botulinum neurotoxin injection into the masseter muscle.

    Science.gov (United States)

    Tsai, Chi-Yang; Chiu, Wan Chi; Liao, Yi-Hsuan; Tsai, Chih-Mong

    2009-02-01

    The effects of botulinum neurotoxin type A (BoNT/A) on masseter muscles, when injected for cosmetic purposes (volumetric reduction) or treatment of excessive muscle activity (bruxism), have been investigated. However, the full anatomic effects of treatment are not known, particularly with respect to the mandible and relevant anthropometric measurements. The intent of this study was to use unilaterial BoNT/A injections to induce localized masseter atrophy and paresis and then to measure the effects of muscle influence on craniofacial growth and development. Growing male Wistar rats, 30 days old, were studied. The experimental group consisted of 8 rats. One side of the masseter muscle was injected with BoNT/A and the other side of the masseter muscle was injected with saline. The side with BoNT/A belonged to 1 group and the side with saline was the sham group. Three rats without injections was the control. After 45 days, the masseter muscles were dissected and weighed. Dry skulls were prepared, and anthropometric measurements determined. One-way ANOVA showed that the animals maintained their weight in both groups; however, the muscles injected with BoNT/A were smaller than the sham or control muscles. Anthropometric measurements of the bony structures attached to the masseter muscle showed a significant treatment effect. After localized masseter muscle atrophy induced by BoNT/A injection, alterations of craniofacial bone growth and development were seen. The results agree with the functional matrix theory that soft tissues regulate bone growth.

  1. MYOSITIS OSSIFICANS TRAUMATICA OF THE MASSETER MUSCLE- review of the literature and case report.

    Directory of Open Access Journals (Sweden)

    Elitsa G. Deliverska

    2013-11-01

    Full Text Available Introduction: Myositis ossificans traumatica (MOT is known mostly in the orthopedic literature as non-neoplastic, heterotopic bone formation within muscle or fascia, presumably due to acute trauma or repeated injury. Myositis ossificans traumatica of the masseter muscle is uncommon disease producing limitation of opening of the jaws. Purpose: To present a case of MOT of the masseter muscle in patient with history of facial trauma. Material and methods: The medical history of a 53 years patient with complaint of decreasing ability to open his mouth over the past 10 years after a blow to face. CT revealed enlarged calcification in the left masseter muscle.Conclusion: Treatment of MOT of the masseter muscle is surgical- total extirpation of the ossified muscle but also surgical techniques including osteotomy that involve the muscle attachment region should be considered and after that appropriate physical therapy.

  2. Cold pressor stimulus temperature and resting masseter muscle haemodynamics in normal humans.

    Science.gov (United States)

    Maekawa, K; Kuboki, T; Clark, G T; Shinoda, M; Yamashita, A

    1998-11-01

    Cold pressor stimulation reportedly increases sympathetic nerve activity in human skeletal muscles. This study examined the effect of cold pressor stimulation on the resting haemodynamics of the right masseter muscle in normal individuals, using near-infrared spectroscopy. Nine healthy non-smoking males with no history of chronic muscle pain or vascular headaches participated. Their right hand was immersed in a water bath (4, 10, 15 degrees C) for exactly 1 min. Each trial lasted 7 min (1 min before, 1 min during, 5 min after stimulation) and a strictly random order was utilized for the three test temperatures and the mock trial. Masseter muscle haemoglobin concentration and oxygen saturation, as well as heart rate and blood pressure, were continuously recorded in each trial. After completing the four trials, each participant produced and sustained a 30-s maximum voluntary clench in the intercuspal position. Data across the four trials were baseline-corrected and then magnitude-normalized to the individual's highest absolute haemoglobin and oxygen signal during the 30-s maximal clenching effort. Haemoglobin and oxygen saturation increased progressively during cold pressor stimulation as the water temperature decreased (Hb, p cold pressor, stimulation induces a strong increase in intramuscular blood volume which appears to be due to both a local vasodilative response and increased cardiac output.

  3. Muscle spindle composition and distribution in human young masseter and biceps brachii muscles reveal early growth and maturation.

    Science.gov (United States)

    Osterlund, Catharina; Liu, Jing-Xia; Thornell, Lars-Eric; Eriksson, Per-Olof

    2011-04-01

    Significant changes in extrafusal fiber type composition take place in the human masseter muscle from young age, 3-7 years, to adulthood, in parallel with jaw-face skeleton growth, changes of dentitions and improvement of jaw functions. As motor and sensory control systems of muscles are interlinked, also the intrafusal fiber population, that is, muscle spindles, should undergo age-related changes in fiber type appearance. To test this hypothesis, we examined muscle spindles in the young masseter muscle and compared the result with previous data on adult masseter spindles. Also muscle spindles in the young biceps brachii muscle were examined. The result showed that muscle spindle composition and distribution were alike in young and adult masseter. As for the adult masseter, young masseter contained exceptionally large muscle spindles, and with the highest spindle density and most complex spindles found in the deep masseter portion. Hence, contrary to our hypothesis, masseter spindles do not undergo major morphological changes between young age and adulthood. Also in the biceps, young spindles were alike adult spindles. Taken together, the results showed that human masseter and biceps muscle spindles are morphologically mature already at young age. We conclude that muscle spindles in the human young masseter and biceps precede the extrafusal fiber population in growth and maturation. This in turn suggests early reflex control and proprioceptive demands in learning and maturation of jaw motor skills. Similarly, well-developed muscle spindles in young biceps reflect early need of reflex control in learning and performing arm motor behavior. Copyright © 2011 Wiley-Liss, Inc.

  4. Short-term effects of dry needling of active myofascial trigger points in the masseter muscle in patients with temporomandibular disorders.

    Science.gov (United States)

    Fernández-Carnero, Josué; La Touche, Roy; Ortega-Santiago, Ricardo; Galan-del-Rio, Fernando; Pesquera, Jorge; Ge, Hong-You; Fernández-de-Las-Peñas, César

    2010-01-01

    To investigate the effects of dry needling over active trigger points (TrPs) in the masseter muscle in patients with temporomandibular disorders (TMD). Twelve females, aged 20 to 41 years old (mean = 25, standard deviation +/- 6 years) diagnosed with myofascial TMD were recruited. Each patient attended two treatment sessions on two separate days and received one intervention assigned in a random fashion, at each visit: deep dry needling (experimental) or sham dry needling (placebo) at the most painful point on the masseter muscle TrP. Pressure pain threshold (PPT) over the masseter muscle TrP and the mandibular condyle and pain-free active jaw opening were assessed pre- and 5 minutes postintervention by an examiner blinded to the treatment allocation of the subject. A two-way repeated-measures analysis of variance (ANOVA) with intervention as the between-subjects variable and time as the within-subjects variable was used to examine the effects of the intervention. The ANOVA detected a significant interaction between intervention and time for PPT levels in the masseter muscle (F = 62.5; P dry needling compared to the sham dry needling (P dry needling into active TrPs in the masseter muscle induced significant increases in PPT levels and maximal jaw opening when compared to the sham dry needling in patients with myofascial TMD.

  5. Protective Effects of Clenbuterol against Dexamethasone-Induced Masseter Muscle Atrophy and Myosin Heavy Chain Transition.

    Science.gov (United States)

    Umeki, Daisuke; Ohnuki, Yoshiki; Mototani, Yasumasa; Shiozawa, Kouichi; Suita, Kenji; Fujita, Takayuki; Nakamura, Yoshiki; Saeki, Yasutake; Okumura, Satoshi

    2015-01-01

    Glucocorticoid has a direct catabolic effect on skeletal muscle, leading to muscle atrophy, but no effective pharmacotherapy is available. We reported that clenbuterol (CB) induced masseter muscle hypertrophy and slow-to-fast myosin heavy chain (MHC) isoform transition through direct muscle β2-adrenergic receptor stimulation. Thus, we hypothesized that CB would antagonize glucocorticoid (dexamethasone; DEX)-induced muscle atrophy and fast-to-slow MHC isoform transition. We examined the effect of CB on DEX-induced masseter muscle atrophy by measuring masseter muscle weight, fiber diameter, cross-sectional area, and myosin heavy chain (MHC) composition. To elucidate the mechanisms involved, we used immunoblotting to study the effects of CB on muscle hypertrophic signaling (insulin growth factor 1 (IGF1) expression, Akt/mammalian target of rapamycin (mTOR) pathway, and calcineurin pathway) and atrophic signaling (Akt/Forkhead box-O (FOXO) pathway and myostatin expression) in masseter muscle of rats treated with DEX and/or CB. Masseter muscle weight in the DEX-treated group was significantly lower than that in the Control group, as expected, but co-treatment with CB suppressed the DEX-induced masseter muscle atrophy, concomitantly with inhibition of fast-to-slow MHC isoforms transition. Activation of the Akt/mTOR pathway in masseter muscle of the DEX-treated group was significantly inhibited compared to that of the Control group, and CB suppressed this inhibition. DEX also suppressed expression of IGF1 (positive regulator of muscle growth), and CB attenuated this inhibition. Myostatin protein expression was unchanged. CB had no effect on activation of the Akt/FOXO pathway. These results indicate that CB antagonizes DEX-induced muscle atrophy and fast-to-slow MHC isoform transition via modulation of Akt/mTOR activity and IGF1 expression. CB might be a useful pharmacological agent for treatment of glucocorticoid-induced muscle atrophy.

  6. Replicability of electromyographic recordings of the masseter muscle during mastication.

    Science.gov (United States)

    Garrett, N R; Kapur, K K

    1986-03-01

    This study evaluates the reliability of a method to duplicate the location of surface electrodes for recording the electromyographic activity of masseter muscles during mastication and quantifying the activity by a microcomputer system. A plastic framework consisting of a bite fork and electrode positioners was used to place the electrodes by relating the positioners to an occlusal index and keeping this relationship constant at subsequent sittings. EMG recordings were repeated on two different days for each of 10 subjects while they performed standardized masticatory performance tests with peanuts and carrots. The muscle activity recorded with hardware integrators was an average of 26.7% of the computerized software integrations but measures derived from the two methods of integration were highly correlated (r = 0.965) and yielded similar results. Significant correlations were found between test sessions for each measure of masticatory performance and integrated EMG activity for ipsilateral and contralateral muscles. For each subject, no significant differences were found between sessions for any masticatory performance or EMG variable. The results indicate that reliable inter session EMG recordings during mastication can be made by using the template for positioning of the electrodes. In addition, the microcomputer data acquisition system provides results comparable to those obtained with conventional hardware integrators, with the added benefit of providing information on each individual stroke and its various components.

  7. Muscle fatigue in the temporal and masseter muscles in patients with temporomandibular dysfunction.

    Science.gov (United States)

    Woźniak, Krzysztof; Lipski, Mariusz; Lichota, Damian; Szyszka-Sommerfeld, Liliana

    2015-01-01

    The aim of this study is to evaluate muscle fatigue in the temporal and masseter muscles in patients with temporomandibular dysfunction (TMD). Two hundred volunteers aged 19.3 to 27.8 years (mean 21.50, SD 0.97) participated in this study. Electromyographical (EMG) recordings were performed using a DAB-Bluetooth Instrument (Zebris Medical GmbH, Germany). Muscle fatigue was evaluated on the basis of a maximum effort test. The test was performed during a 10-second maximum isometric contraction (MVC) of the jaws. An analysis of changes in the mean power frequency of the two pairs of temporal and masseter muscles (MPF%) revealed significant differences in the groups of patients with varying degrees of temporomandibular disorders according to Di (P muscle fatigue of the temporal and masseter muscles correlated with the intensity of temporomandibular dysfunction symptoms in patients. The use of surface electromyography in assessing muscle fatigue is an excellent diagnostic tool for identifying patients with temporomandibular dysfunction.

  8. Muscle Fatigue in the Temporal and Masseter Muscles in Patients with Temporomandibular Dysfunction

    Directory of Open Access Journals (Sweden)

    Krzysztof Woźniak

    2015-01-01

    Full Text Available The aim of this study is to evaluate muscle fatigue in the temporal and masseter muscles in patients with temporomandibular dysfunction (TMD. Two hundred volunteers aged 19.3 to 27.8 years (mean 21.50, SD 0.97 participated in this study. Electromyographical (EMG recordings were performed using a DAB-Bluetooth Instrument (Zebris Medical GmbH, Germany. Muscle fatigue was evaluated on the basis of a maximum effort test. The test was performed during a 10-second maximum isometric contraction (MVC of the jaws. An analysis of changes in the mean power frequency of the two pairs of temporal and masseter muscles (MPF% revealed significant differences in the groups of patients with varying degrees of temporomandibular disorders according to Di (P<0.0000. The study showed an increase in the muscle fatigue of the temporal and masseter muscles correlated with the intensity of temporomandibular dysfunction symptoms in patients. The use of surface electromyography in assessing muscle fatigue is an excellent diagnostic tool for identifying patients with temporomandibular dysfunction.

  9. Muscle Fatigue in the Temporal and Masseter Muscles in Patients with Temporomandibular Dysfunction

    Science.gov (United States)

    Woźniak, Krzysztof; Lipski, Mariusz; Lichota, Damian

    2015-01-01

    The aim of this study is to evaluate muscle fatigue in the temporal and masseter muscles in patients with temporomandibular dysfunction (TMD). Two hundred volunteers aged 19.3 to 27.8 years (mean 21.50, SD 0.97) participated in this study. Electromyographical (EMG) recordings were performed using a DAB-Bluetooth Instrument (Zebris Medical GmbH, Germany). Muscle fatigue was evaluated on the basis of a maximum effort test. The test was performed during a 10-second maximum isometric contraction (MVC) of the jaws. An analysis of changes in the mean power frequency of the two pairs of temporal and masseter muscles (MPF%) revealed significant differences in the groups of patients with varying degrees of temporomandibular disorders according to Di (P < 0.0000). The study showed an increase in the muscle fatigue of the temporal and masseter muscles correlated with the intensity of temporomandibular dysfunction symptoms in patients. The use of surface electromyography in assessing muscle fatigue is an excellent diagnostic tool for identifying patients with temporomandibular dysfunction. PMID:25883949

  10. [Electromyographic (EMG) electrode impedance and EMG activity from anterior temporal muscle and masseter muscle].

    Science.gov (United States)

    Takarada, T; Alvarado Larrinaga, G; Nishida, F; Nishino, M

    1989-01-01

    The value and change with time of the impedance of surface EMG electrodes and the effects of their difference between the bipolar electrodes on the electromyographic activity from the anterior temporal muscle and the masseter muscle in six adult male subjects with normal occlusion were studied. The results were as follows: 1. In the anterior temporal muscle, if the impedance of the electrode was under 20 k omega it was stable from just after the electrode disc was applied to the skin. In the masseter muscle, if the impedance was under 30 k omega it became stable within two minutes after the electrode was applied. 2. The difference of impedance between the bipolar EMG electrodes did not correlate with EMG activity.

  11. Electromyographic analysis of masseter muscle in newborns during suction in breast, bottle or cup feeding

    National Research Council Canada - National Science Library

    França, Ellia C L; Sousa, Cejana B; Aragão, Lucas C; Costa, Luciane R

    2014-01-01

    .... The aim of this study was to analyze the electrical activity of the masseter muscle using surface electromyography during suction in term newborns by comparing breastfeeding, bottle and cup feeding...

  12. Simultaneous Bilateral Hypertrophies of the Parotid Gland and Masseter Muscle: Case Report.

    Science.gov (United States)

    Prabhu, Rohan; Mandel, Louis

    2017-01-01

    Increased salivary demand can lead to enlarged parotid salivary glands, and increased activity of the masseter muscles can cause masseter hypertrophy. This report describes a most unusual case of simultaneous bilateral hypertrophies of the parotid gland and masseter muscle originating from the very extensive habit of chewing gum. An extensive literature review uncovered many cases of the independent existence of masseteric or parotid hypertrophy, but no example of the simultaneous occurrence of these 2 conditions. Copyright © 2016 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

  13. Reduced masticatory function is related to lower satellite cell numbers in masseter muscle.

    Science.gov (United States)

    Kuijpers, M A R; Grefte, S; Bronkhorst, E M; Carels, C E L; Kiliaridis, S; Von den Hoff, J W

    2014-06-01

    The physiology of masseter muscles is known to change in response to functional demands, but the effect on the satellite cell (SC) population is not known. In this study, the hypothesis is tested that a decreased functional demand of the masseter muscle causes a reduction of SCs. To this end, twelve 5-week-old male Sprague-Dawley rats were put on a soft diet (SD, n = 6) or a hard diet (HD, n = 6) and sacrificed after 14 days. Paraffin sections of the superficial masseter and the m. digastricus (control muscle) were stained with haematoxylin and eosin for tissue survey and with anti-myosin heavy chain (MHC) for slow and fast fibres. Frozen sections of both muscles were double-stained for collagen type IV and Pax7. Slow MHC fibres were equally distributed in the m. digastricus but only localized in a small area of the m. masseter. No differences between HD or SD for the m. digastricus were found. The m. masseter had more SCs per fibre in HD than in SD (0.093 ± 0.007 and 0.081 ± 0.008, respectively; P = 0.027). The m. masseter had more fibres per surface area than the m. digastricus in rats with an SD group (758.1 ± 101.6 and 568.4 ± 85.6, P = 0.047) and a HD group (737.7 ± 32.6 and 592.2 ± 82.2; P = 0.007). The m. digastricus had more SCs per fibre than the m. masseter in the SD group (0.094 ± 0.01 and 0.081 ± 0.008; P = 0.039). These results suggest that reduced masseter muscle function is related to a lower number of SCs. Reduced muscle function might decrease microdamage and hence the requirement of SCs in the muscle fibres.

  14. 肌筋膜疼痛伴开口受限患者咬肌肌电图研究%Electromyography Analysis on Masseter Muscles in Myofacial Pain Syndrome Patients with Limited Mouth Opening

    Institute of Scientific and Technical Information of China (English)

    张非煜; 吕亚林; 董坚; 张杰夫; 李俨

    2013-01-01

    Objective: To analyze the surface electromyography (EMG) data of masseter muscles (MM) in patients with temporomandibular joint myofascial pain and anterior disk displacement without reduction (ADDWR). Methods: Twenty patients diagnosed with muscular TMD( ADDWR) by clinical examination were selected as experimental group. Ten people checked without TMD were selected as contrast group. EMG data MM of both groups were recorded and analyzed at mandibular postural position (MPP) and maximum contacted intercuspal position (ICP). The data were analyzed by 2 -way repeated-measures ANOVA and means were compared by SNK test (P<0. 05). Results: At MPP,patients' EMG potentials showed the significantly greater root mean square (RMS) of bilateral MM comparing with those of the control group MM (P<0. 01). At ICP, RMS of the bilateral MM of the experimental group was significantly less (P<0. 01). At MPP,patients' median frequency (MF) shows significantly less (P

  15. [Muscle action potential and masticatory rhythm of anterior temporal and masseter muscles in children and adults].

    Science.gov (United States)

    Alvarado Larrinaga, G; Takarada, T; Nishida, F; Nishino, M

    1989-01-01

    For the investigation of the functional change of the masticatory muscles along with growth and development, electromyographic evaluation was carried out. The subjects were 6 children (5 males and 1 female) with full deciduous dentition (Hellman's dental age IIA) aged 4.5 +/- 0.2 years and 6 adults (4 males and 2 females) with full permanent dentition aged 27.7 +/- 3.8 years. EMG signals were recorded bilaterally by means of bipolar silver surface electrodes from the anterior temporal and masseter muscles when the subjects were chewing chewing gum or performing maximum clenches in intercuspal position. The cumulative power values from 62.5 to 1000 Hz in the EMG power spectrum during chewing or clenching were calculated as the muscle action potential. The ratio of the action potential of each muscle to the total action potential of four muscles were analyzed. Masticatory rhythm during chewing was analyzed by means of the time parameter (duration, interval and cycle) and their coefficients of variation. The results were as follows: 1. In children the temporal muscles predominated in chewing and clenching, whereas in adults there were three types with Temporal muscles predominating, Masseter muscles predominating and both muscles sharing equally. 2. No statistically significant differences between children and adults were observed in the duration, interval and cycle. 3. In adults the coefficients of variation of the duration, interval and cycle were smaller and the masticatory rhythm was more stable than in children.

  16. Macrophages and mast cells in dystrophic masseter muscle: a light and electron microscopic study

    DEFF Research Database (Denmark)

    Kirkeby, S; Mikkelsen, H

    1988-01-01

    Macrophages and mast cells in masseter muscle from normal and dystrophic mice were studied by light and electron microscopy. Acid phosphatase activity and FITC-dextran were used to identify and describe macrophages. Toluidine blue was used as a marker for mast cells. In dystrophic muscle, the num......Macrophages and mast cells in masseter muscle from normal and dystrophic mice were studied by light and electron microscopy. Acid phosphatase activity and FITC-dextran were used to identify and describe macrophages. Toluidine blue was used as a marker for mast cells. In dystrophic muscle...

  17. Feasibility of eliciting the H reflex in the masseter muscle in patients under general anesthesia.

    Science.gov (United States)

    Ulkatan, Sedat; Jaramillo, Ana Maria; Téllez, Maria J; Goodman, Robert R; Deletis, Vedran

    2017-01-01

    To explore the feasibility of eliciting the brainstem H reflex in the masseter muscle in patients under general anesthesia. We electrically stimulated the masseteric nerve, a branch of the trigeminal nerve, and recorded ipsilateral masseteric and temporalis muscle responses. We tested eight patients who presented with trigeminal neuralgia; one patient had a temporal bone tumor and one patient had a brainstem arteriovenous malformation. All responses were elicited when patients were under general anesthesia and before the initiation of surgery. The H reflex in the masseter muscle was reliably elicited in 70% of the patients. The reflexes met the usual criteria for the H reflex because they were elicited below the threshold of the direct M response, and their amplitudes decreased when the M response increased with stronger stimuli. The mean onset latencies of the masseter H reflex and the M response were 5.4±1.3ms and 2.6±0.6ms, respectively. In the present study, we provide evidence of the feasibility of eliciting the H reflex in the masseter muscles of patients under general anesthesia. The H reflex of the masseter muscle may represent a new method available for intraoperative monitoring. Specifically, this method may be important for the monitoring of brainstem functional integrity, particularly in the midbrain and mid-pons, in addition to the trigeminal nerve path. Copyright © 2016 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

  18. Masseter Muscle Activity in Track and Field Athletes: A Pilot Study

    Science.gov (United States)

    Nukaga, Hideyuki; Takeda, Tomotaka; Nakajima, Kazunori; Narimatsu, Keishiro; Ozawa, Takamitsu; Ishigami, Keiichi; Funato, Kazuo

    2016-01-01

    Teeth clenching has been shown to improve remote muscle activity (by augmentation of the Hoffmann reflex), and joint fixation (by decreased reciprocal inhibition) in the entire body. Clenching could help maintain balance, improve systemic function, and enhance safety. Teeth clenching from a sports dentistry viewpoint was thought to be important and challenging. Therefore, it is quite important to investigate mastication muscles’ activity and function during sports events for clarifying a physiological role of the mastication muscle itself and involvement of mastication muscle function in whole body movement. Running is a basic motion of a lot of sports; however, a mastication muscles activity during this motion was not clarified. Throwing and jumping operation were in a same situation. The purpose of this study was to investigate the presence or absence of masseter muscle activity during track and field events. In total, 28 track and field athletes took part in the study. The Multichannel Telemetry system was used to monitor muscle activity, and the electromyograms obtained were synchronized with digital video imaging. The masseter muscle activity threshold was set 15% of maximum voluntary clenching. As results, with few exceptions, masseter muscle activity were observed during all analyzed phases of the 5 activities, and that phases in which most participants showed masseter muscle activity were characterized by initial acceleration, such as in the short sprint, from the commencement of throwing to release in both the javelin throw and shot put, and at the take-off and landing phases in both jumps. PMID:27708727

  19. Effects of experimental nasal obstruction on human masseter and suprahyoid muscle activities during sleep.

    Science.gov (United States)

    Hiyama, Shigetoshi; Ono, Takashi; Ishiwata, Yasuo; Kuroda, Takayuki; Ohyama, Kimie

    2003-04-01

    The effect of nasal obstruction on nocturnal masseter and suprahyoid muscle activities using a newly developed portable electromygram (EMG)-recording unit was examined. Ten healthy Japanese males participated in this study. EMG activities of both the right masseter and bilateral suprahyoid muscles were recorded with a portable EMG-recording unit. At midnight, the subject was asked to lie on a bed after complete preparation with surface electrodes. After maximal clenching and jaw-opening effort (100% maximum voluntary contribution), the subject was allowed to fall asleep. In the first half of the night, EMG activities were recorded for about three hours of sleep without nasal obstruction. In the second half of the night, EMG activities were recorded for about three hours of sleep with nasal obstruction. In both muscles, there were no significant changes in either the maximal EMG activities or the number of events beyond 40% MVC with nasal obstruction. But in an evaluation based on the distribution of muscle activities, the EMG activity of the masseter muscle tended to decrease (P = .07) and that of the suprahyoid muscles increased significantly (P = .02) with nasal obstruction. These results suggest that nasal obstruction could modulate the activities of the masseter and suprahyoid muscles during sleep.

  20. Botulinum neurotoxin type A in the masseter muscle: Effects on incisor eruption in rabbits

    Science.gov (United States)

    Navarrete, Alfonso L.; Rafferty, Katherine L.; Liu, Zi Jun; Ye, Wenmin; Greenlee, Geoffrey M.; Herring, Susan W.

    2015-01-01

    Introduction Botulinum neurotoxins are responsible for the paralytic food poisoning, botulism. Commercial formulations such as botulinum neurotoxin type A are increasingly used for various conditions, including cosmetic recontouring of the lower face by injection of the large masseter muscles. The paralysis of a major muscle of mastication lowers occlusal force and thus might affect tooth eruption. The purpose of this study was to investigate the effects of unilateral masseter muscle injection of botulinum neurotoxin type A on the rate of eruption of incisors in a rabbit model. We hypothesized that the teeth would overerupt in an underloaded environment. Methods Forty rabbits were injected with either botulinum neurotoxin type A or saline solution in 1 masseter muscle. Mastication and muscle force production were monitored, and incisor eruption rate was assessed by caliper measurement of grooved teeth. Results The injection of saline solution had no effect. The masseter muscle injected with botulinum neurotoxin type A showed a dramatic loss of force 3 weeks after injection despite apparently normal mastication. Incisor eruption rate was significantly decreased for the botulinum neurotoxin type A group, an effect attributed to decreased attrition. Conclusions This study has implications for orthodontics. Although findings from ever-growing rabbit incisors cannot be extrapolated to human teeth, it is clear that botulinum neurotoxin type A caused a decrease in bite force that could influence dental eruption. PMID:23561411

  1. Nerve growth factor alters the sensitivity of rat masseter muscle mechanoreceptors to NMDA receptor activation.

    Science.gov (United States)

    Wong, Hayes; Dong, Xu-Dong; Cairns, Brian E

    2014-11-01

    Intramuscular injection of nerve growth factor (NGF) into rat masseter muscle induces a local mechanical sensitization that is greater in female than in male rats. The duration of NGF-induced sensitization in male and female rats was associated with an increase in peripheral N-methyl-d-aspartate (NMDA) receptor expression by masseter muscle afferent fibers that began 3 days postinjection. Here, we investigated the functional consequences of increased NMDA expression on the response properties of masseter muscle mechanoreceptors. In vivo extracellular single-unit electrophysiological recordings of trigeminal ganglion neurons innervating the masseter muscle were performed in anesthetized rats 3 days after NGF injection (25 μg/ml, 10 μl) into the masseter muscle. Mechanical activation threshold was assessed before and after intramuscular injection of NMDA. NMDA injection induced mechanical sensitization in both sexes that was increased significantly following NGF injection in the male rats but not in the female rats. However, in female but not male rats, further examination found that preadministration of NGF induced a greater sensitization in slow Aδ-fibers (2-7 m/s) than fast Aδ-fibers (7-12 m/s). This suggests that preadministration of NGF had a different effect on slowly conducting mechanoreceptors in the female rats compared with the male rats. Although previous studies have found an association between estrogenic tone and NMDA activity, no correlation was observed between NMDA-evoked mechanical sensitization and plasma estrogen level. This study suggests NGF alters NMDA-induced mechanical sensitization in the peripheral endings of masseter mechanoreceptors in a sexually dimorphic manner.

  2. An Eectromyographic Ccomparison Between the Activities of Temporal and Masseter Muscles in Class III Skeletal

    Directory of Open Access Journals (Sweden)

    T Hossein-Zadeh-Nik

    2002-02-01

    Full Text Available Electromyographic (EMG investigations about the activities of the muscles have been the focus of attention for many years. In the field of orthodontics, investigators, among other things, tried to evaluate correlation between EMG activity, occlusal relationships and craniofacial morphology to analyze the effect of muscular activity, as an etiological factor in malocclusion. The purpose of the present investigation is to analyze the effect of EMG activity of temporal and masseter muscles quantitatively in skeletal class III malocclusion. 26 patients (9 to If years old, with class III malocclusion were selected and their EMG activity of temporal and masseter muscles in rest position, centric occlusion, clenching, mastication and swallowing were compared with 20 normal children at the same age range. Then the statistical correlation between 13 cephalometric parameters and EMG activities were analyzed and then the regression analysis was performed and the results were as follows:1- The mean amplitude of masseter and temporal muscles activity in rest position, centric occlusion, mastication, and clenching in class III samples were greater than normal group (PO.05.2- The mean duration of masseter and temporal muscles activity in rest position and centric occlusion in class III samples were more than normal group (PO.05.3- According to regression analysis, a linear correlation was observed between ANB angle and temporal muscle activity in rest and centric occlusion that was not observed in other cases.The findings of this study showed that difference in temporal muscle activity in class III malocclusion, in comparison with the normal group, is correlated with skeletal morphology of the face, but according to other investigations it is not ture for the masseter muscle.

  3. Comparative data from young men and women on masseter muscle fibres, function and facial morphology

    DEFF Research Database (Denmark)

    Tuxen, A.; Bakke, M.; Pinholt, E. M.

    1999-01-01

    The primary aim was to relate information about masseter muscle fibres and function to aspects of facial morphology in a group of healthy young men. The secondary aim was to investigate possible sex differences using data previously obtained from a comparable group of age-matched, healthy women....... Dental status and facial morphology were recorded in 13 male students aged 20-26 years. Functional examinations included bite-force measurements and electromyographic recordings of masseter activity. A biopsy was removed from the masseter of each participant during surgical extraction of a wisdom tooth......, and the tissue examined for myosin ATPase activity. Further, the cross-sectional areas of the different fibre types were measured. In spite of using age-matched healthy men and women with a full complement of teeth, statistically significant sex differences were found among measures related to muscle function...

  4. Body position effects on EMG activity of sternocleidomastoid and masseter muscles in healthy subjects.

    Science.gov (United States)

    Miralles, R; Palazzi, C; Ormeño, G; Giannini, R; Verdugo, F; Valenzuela, S; Santander, H

    1998-04-01

    This study was conducted in order to determine the effects of body position on integrated electromyographic (IEMG) activity of sternocleidomastoid and masseter muscles in 20 healthy subjects. EMG recordings at rest and during swallowing of saliva and maximal voluntary clenching were performed by placing surface electrodes on the sternocleidomastoid and masseter muscles (contralateral to the habitual side of sleeping of each subject), in the following body positions: standing, seated, supine, and lateral decubitus position. Significant higher EMG activities were recorded in the sternocleidomastoid muscle in the lateral decubitus position, whereas significant lower EMG activities were recorded in the masseter muscle in the supine position. This finding supports the idea that there may exist a differential modulation of the motor neuron pools of the sternocleidomastoid and masseter muscles of peripheral and/or central origin. Significant differences in the EMG pattern as well as in the levels of EMG activities upon variations in body positions were observed between healthy subjects and patients with myogenic craniomandibular dysfunction reported by Palazzi, et al.

  5. Differential activity patterns in the masseter muscle under simulated clenching and grinding forces.

    Science.gov (United States)

    Schindler, H J; Türp, J C; Blaser, R; Lenz, J

    2005-08-01

    The aim of this study was to investigate (i) whether the masseter muscle shows differential activation under experimental conditions which simulate force generation during clenching and grinding activities; and (ii) whether there are (a) preferentially active muscle regions or (b) force directions which show enhanced muscle activation. To answer these questions, the electromyographic (EMG) activity of the right masseter muscle was recorded with five intramuscular electrodes placed in two deep muscle areas and in three surface regions. Intraoral force transfer and force measurement were achieved by a central bearing pin device equipped with three strain gauges (SG). The activity distribution in the muscle was recorded in four different mandibular positions (central, left, right, anterior). In each position, maximum voluntary contraction (MVC) was exerted in vertical, posterior, anterior, medial and lateral directions. The investigated muscle regions showed different amount of EMG activity. The relative intensity of the activation, with respect to other regions, changed depending on the task. In other words, the muscle regions demonstrated heterogeneous changes of the EMG pattern for the various motor tasks. The resultant force vectors demonstrated similar amounts in all horizontal bite directions. Protrusive force directions revealed the highest relative activation of the masseter muscle. The posterior deep muscle region seemed to be the most active compartment during the different motor tasks. The results indicate a heterogeneous activation of the masseter muscle under test conditions simulating force generation during clenching and grinding. Protrusively directed bite forces were accompanied by the highest activation in the muscle, with the posterior deep region as the most active area.

  6. A intervenção fonoaudiológica no pós-operatório da hipertrofia benigna do músculo masseter The miofunctional oral intervention in the surgery treatment for the masseter muscle hipertrophy

    Directory of Open Access Journals (Sweden)

    Laura Davison Mangilli

    2006-04-01

    Full Text Available OBJETIVO: descrever a abordagem fonoaudiológica no pós-operatório de pacientes que realizaram correção cirúrgica da hipertrofia do músculo masseter. METODOLOGIA: foram coletados dados referentes à avaliação e ao tratamento fonoaudiológico de 4 prontuários de sujeitos de ambos os gêneros, com faixa etária entre 16 e 24 anos, com hipertrofia benigna do músculo masseter, tratados cirurgicamente. RESULTADOS: as principais queixas pós-cirúrgicas estiveram relacionadas à limitação da abertura da boca, à dor na região da cirurgia, à rigidez muscular e a estalo em região da ATM. A terapia fonoaudiológica baseou-se em orientação quanto à retirada de hábitos deletérios; termoterapia na região do músculo masseter; manipulação da musculatura envolvida extra e intrabucais; alongamento da musculatura facial e cervical; alavanca de abertura forçada de boca e exercícios de órgãos fonoarticulatórios. CONCLUSÕES: a terapia fonoaudiológica apresenta-se como uma possibilidade de complementação ao tratamento cirúrgico, na adequação da amplitude dos movimentos mandibulares, assim como na eliminação dos sintomas presentes no pós-cirúrgico e na conscientização dos hábitos deletérios, que são apontados pela literatura como possíveis fatores desencadeantes.AIM: the aim of this study was to describe miofunctional oral intervention in patients with Masseter muscle hipertrophy treated by surgery. METHODS: the sample consisted of 4 patients, male and female, with ages between 16 and 24 years, with Masseter muscle hipertrophy treated by surgery. RESULTS: the main complains on the postoperative were related to trismus, muscle rigidity, and clicking in the temporomandibular joint. The myofunctional oral therapy was based on orientation in the abnormal habits (bruxism, clenching elimination, hyperthermia induced in the masseter muscle, oral muscles massage, facial and cervical muscles stretching, miofunctional exercises and

  7. Spatiotemporal Profiles of Proprioception Processed by the Masseter Muscle Spindles in Rat Cerebral Cortex: An Optical Imaging Study

    Science.gov (United States)

    Fujita, Satoshi; Kaneko, Mari; Nakamura, Hiroko; Kobayashi, Masayuki

    2017-01-01

    processed in a region that is adjacent to these pulpal regions and is located in the rostral part of S2/IOR, which receives nociceptive inputs from the molar pulps. The spatial proximity of these regions may be associated with the mechanisms by which masseter muscle pain is incorrectly perceived as dental pain. PMID:28194098

  8. Effects of muscle pain induced by glutamate injections during sustained clenching on the contraction pattern of masticatory muscles.

    Science.gov (United States)

    Michelotti, Ambrosina; Cioffi, Iacopo; Rongo, Roberto; Borrelli, Roberta; Chiodini, Paolo; Svensson, Peter

    2014-01-01

    To evaluate the contraction pattern of masticatory muscles during sustained clenching tasks with or without experimental pain induced by glutamate injection into the masseter muscle. It was hypothesized that acute muscle pain could induce compensatory changes in the electromyographic (EMG) activity of the masticatory muscles. Fifteen volunteers (seven males, mean age ± SD = 29.7 ± 1.1 years; eight females, mean age ± SD = 23.5 ± 1.2 years) were recruited in a crossover experimental study. All subjects participated in two randomized 20-minute experimental sessions. Each subject was asked to clench at 25% of the maximum voluntary contraction (MVC). After 10 minutes, isotonic saline or glutamate was injected in random order into the right masseter. EMG activity (root mean square [RMS] and mean power frequency [MPF]) was assessed in the masseter and anterior temporalis muscles on both sides. Pain and fatigue were assessed by 0-10 numeric rating scales (NRS) every minute. Differences between conditions (isotonic saline vs glutamate) for all the outcome parameters were analyzed by using a mixed effect model. The EMG activity of the masticatory muscles and pain and fatigue scores were not dependent on isotonic saline/glutamate injection (all P > .05). The RMS in the temporalis and masseter muscles increased with time (right masseter P = 0.001, left masseter P = .004, right temporalis P = .22, left temporalis P = .006), whereas the MPF decreased (right masseter P = .0001, left masseter P muscles during a sustained clenching task. This finding strongly suggests the adaptive capacity of the stomatognathic system in the presence of acute nociceptive inputs.

  9. The contribution of the deep fibers of the masseter muscle to selected tooth-clenching and chewing tasks.

    Science.gov (United States)

    Belser, U C; Hannam, A G

    1986-11-01

    Anatomically, the human masseter muscle consists of at least two portions (pars superficialis, pars profunda) with distinctly different fiber directions. The purpose of this study was to describe functional behavior in the deep fibers of the masseter muscle and to define any differences in its behavior from that of the superficial fibers. In 20 subjects, EMG activity of the superficial and the deep portions of the masseter muscle was recorded during specific parafunctional (intercuspal and eccentric tooth clenching) and functional (unilateral chewing) tests. Superficial and deep activity was measured with bipolar surface electrodes and intramuscular fine-wire electrodes. Simultaneously, displacement of a lower incisor point was recorded in three dimensions. The data were collected and stored for analysis by a disk-based computer system. The results indicated that changes in the direction of effort, in mandibular position, and in the side used for chewing all influenced activity in both parts of the muscle to different extents. The most distinct separation of activity occurred when intercuspal clenching was directed retrusively; the deep fibers of the masseter muscle response reduced to 47.5% of its maximum value while that of the superficial fibers of the masseter muscle fell to 5.5%. During chewing, activity in the deep fibers of masseter muscle was distributed evenly bilaterally, whereas that in the superficial fibers of the masseter muscle was biased significantly toward the chewing side. Differentiation of activity within the masseter muscle may be relevant to the distribution of regional tenderness in the muscle when it is involved in parafunctional activity.(ABSTRACT TRUNCATED AT 250 WORDS)

  10. Electromyographic and ultrasonographic evaluation of the masseter muscle individuals with unilateral peripheral facial paralysis

    Directory of Open Access Journals (Sweden)

    Sassi, Fernanda Chiarion

    2011-10-01

    Full Text Available Introduction: Individuals with peripheral Facial Paralysis (FP show conditions that lead to unilateral mastication, performed by the non-affected side, mainly due to the difficulty of action of the buccinator muscle. Objectives: characterize the motor control and morphology of the masseter muscle in individuals with unilateral peripheral FP through electromyographic and ultrasonographic evaluation. Method: 16 participants, of both sexes, with ages superior to 18 years old. The study group (SG consisted of 8 individuals who'd had idiopathic unilateral peripheral FP for more than 6 months; the control group (CG consisted of 8 normal individuals. All the subjects were submitted to the masseter muscle evaluation through surface electromyography (sEMG and ultrasonography (USG during the following tasks: rest, clenching with cotton roller between the teeth (CT and clenching with maximum intercuspation (MIC. Results: There was no statistically significant difference in comparisons within and between the groups concerning the hemifacial asymmetry, both for the sEMG and for the USG. Also there were no significant differences in the activation of the masticatory muscles (masseter and temporal in the sEMG. Conclusions: Both the motor control and the morphology of the masseter muscles in individuals with unilateral peripheral FP were similar to those of normal individuals. Although literature suggests that the demand of functional adaptations made by FP individuals could exceed the structural and functional tolerance of the temporomandibular joints, the results indicate that the length of analyzed patient's FP was not enough to generate anatomical and physiological differences in the masticatory muscles.

  11. Evaluation of sexual dimorphism and the relationship between craniofacial, dental arch and masseter muscle characteristics in mixed dentition

    OpenAIRE

    Marquezin, Maria Carolina Salomé; Andrade, Annicele da Silva; Rossi, Moara de; Gameiro, Gustavo Hauber; Gavião, Maria Beatriz Duarte; Castelo,Paula Midori

    2014-01-01

    Purpose: to evaluate sexual dimorphism and the relationship between craniofacial characteristics, dental arch morphology and masseter muscle thickness in children in the mixed dentition stage. Methods: the study sample comprised 32 children, aged 6-10 years (14♀/18♂) with normal occlusion. Craniofacial characteristics, dental morphology and masseter muscle thickness were evaluated by means of posteroanterior cephalometric radiographs, dental cast evaluation and ultrasound exam, respectively. ...

  12. Ultrastructural features of masseter muscle exhibiting altered occlusal relationship—a study in a rodent model

    Science.gov (United States)

    Lisboa, Marcio V.; Aciole, Gilberth T. S.; Oliveira, Susana C. P. S.; Marques, Aparecida M. C.; Baptista, Abrahão F.; Pinheiro, Antonio L. B.; Aguiar, Marcio C.; Santos, Jean N.

    2010-05-01

    The role of occlusion on Tempormandibular Disorders (TMD) is still unclear, mainly regarding muscular function. The aim of this study was to evaluate the occlusion highlights on masseter ultra morphology. Twenty Wistar rats were randomly divided in four groups: 10 for control group, 10 for occlusal alteration group (CCO). Rats underwent unilateral amputation of the left inferior and superior molar cusps to simulate an occlusal wear situation. The rats of control group had no occlusal wear. Half of the animals of each group was sacrificed in 14 days after the occlusal consuming and half 30 days after the occlusal consuming. The masseter muscles ipsilateral to the amputated molars were excised and processed for light microscopy, electron microscopy. The light microscopy did not show differences between the groups. The electron microscopy was able to detect a degree of intracellular damage in muscle fibers of CCO group: swollen mitochondria with disrupted cristae and cleared matrix, signs of hypercontraction of I bands and myofibril disorganization.

  13. A Modelling of Normal and Abnormal EMG Silent Period Generation of Masseter Muscle

    Energy Technology Data Exchange (ETDEWEB)

    Kim, T.H.; Jeon, C.I. [University Of Seoul, Seoul (Korea); Lee, S.H. [Induk Institute of Technology, Seoul (Korea)

    2003-02-01

    This paper proposes a model of SP(silent period) generation in masseter muscle by means of computer simulation. The model is based on the anatomical and physiological properties of trigeminal nervous system. In determining the SP generation pathway, evoked SPs of masseter muscle after mechanical stimulation to the chin are divided into normal and abnormal group. Normal SP is produced by the activation of mechanoreceptors in periodontal ligament. The activation of nociceptors contributes to the latter part of normal SP, abnormal extended SP is produced. As a result, the EMG signal generated by a proposed SP generation model is similar to both real EMG signal including normal SP and abnormal extended SP with TMJ patients. The result of this study have shown differences of SP generation mechanism between subjects both with and without TMJ dysfunction. (author). 21 refs., 12 figs., 1 tab.

  14. Effect of triiodothyronine on the maxilla and masseter muscles of the rat stomatognathic system

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    M.V. Mariúba

    2011-07-01

    Full Text Available The maxilla and masseter muscles are components of the stomatognathic system involved in chewing, which is frequently affected by physical forces such as gravity, and by dental, orthodontic and orthopedic procedures. Thyroid hormones (TH are known to regulate the expression of genes that control bone mass and the oxidative properties of muscles; however, little is known about the effects of TH on the stomatognathic system. This study investigated this issue by evaluating: i osteoprotegerin (OPG and osteopontine (OPN mRNA expression in the maxilla and ii myoglobin (Mb mRNA and protein expression, as well as fiber composition of the masseter. Male Wistar rats (~250 g were divided into thyroidectomized (Tx and sham-operated (SO groups (N = 24/group treated with T3 or saline (0.9% for 15 days. Thyroidectomy increased OPG (~40% and OPN (~75% mRNA expression, while T3 treatment reduced OPG (~40% and OPN (~75% in Tx, and both (~50% in SO rats. Masseter Mb mRNA expression and fiber type composition remained unchanged, despite the induction of hypo- and hyperthyroidism. However, Mb content was decreased in Tx rats even after T3 treatment. Since OPG and OPN are key proteins involved in the osteoclastogenesis inhibition and bone mineralization, respectively, and that Mb functions as a muscle store of O2 allowing muscles to be more resistant to fatigue, the present data indicate that TH also interfere with maxilla remodeling and the oxidative properties of the masseter, influencing the function of the stomatognathic system, which may require attention during dental, orthodontic and orthopedic procedures in patients with thyroid diseases.

  15. Clinical significance of isometric bite force versus electrical activity in temporal and masseter muscles

    DEFF Research Database (Denmark)

    Bakke, Merete; Michler, L; Han, K

    1989-01-01

    Bite force and activity in temporal and masseter muscles during biting and chewing were recorded in 19 control subjects and 23 subjects with symptoms and signs of functional disorders of the craniomandibular system. The entire group comprised 13 men and 29 women, 14-63 yr of age. Maximal unilater...... of mandibular elevator strength as a whole, but inadequate to disclose asymmetric conditions. During isometric contraction, relative strength of electromyographic activity fairly accurately imaged the output of mechanical activity....

  16. Masseter length determines muscle spindle reflex excitability during jaw-closing movements.

    Science.gov (United States)

    Naser-Ud-Din, Shazia; Sowman, Paul F; Sampson, Wayne J; Dreyer, Craig W; Türker, Kemal Sitki

    2011-04-01

    The masticatory muscles are considered to be important determinants of facial form, but little is known of the muscle spindle reflex characteristics and their relationship, if any, to face height. The aim of this study was to determine whether spindle reflexes, evoked by mechanical stimulation of an incisor and recorded on the masseter muscle, correlated with different facial patterns. Twenty-eight adult volunteers (16 women; ages, 19-38 years) underwent 2-N tap stimuli to their maxillary left central incisor during simulated mastication. Reflexes were recorded during local anesthesia of the stimulated tooth to eliminate the contribution from periodontal mechanoreceptors. Surface electromyograms of the reflex responses of the jaw muscles to these taps were recorded via bipolar electrodes on the masseter muscle and interpreted by using spike-triggered averaging of the surface electromyograms. Lateral cephalometric analysis was carried out with software (version 10.5, Dolphin, Los Angeles, Calif; and Mona Lisa, Canberra, Australia). Two-newton tooth taps produced principally excitatory reflex responses beginning at 17 ms poststimulus. Correlation analysis showed a significant relationship between these muscle spindle reflexes and facial heights: specifically, shorter face heights were associated with stronger spindle reflexes. This correlation was strongest between the derived measure of masseter length and the spindle reflex strength during jaw closure (r = -0.49, P = 0.008). These results suggest that a similar muscle spindle stimulus will generate a stronger reflex activation in the jaw muscles of patients with shorter faces compared with those with longer faces. This finding might help to explain the higher incidence of clenching or bruxism in those with short faces and also might, in the future, influence the design of orthodontic appliances and dental prostheses. Copyright © 2011 American Association of Orthodontists. Published by Mosby, Inc. All rights

  17. Comparative study of excitation patterns in the masseter muscle before and after orthognathic surgery.

    Science.gov (United States)

    Eckardt, L; Harzer, W; Schneevoigt, R

    1997-12-01

    This study was designed to inquire into changes occurring in the electromyographic activity throughout the masseter muscle after orthognathic surgical treatment of various bite anomalies. A total of 32 adult patients showing distinct class II (n = 15) or class III malocclusions (n = 17) were entered into the investigation. All patients had monopolar surface electromyograms of the masseter muscle taken prior to presurgical orthodontic treatment and after removal of their orthodontic appliances after surgery. Twenty eugnathic adult patients served as controls. Unlike bipolar lead readings, simultaneous sampling from 16 electrodes permits the registration of the overall excitation pattern in the entire muscle. Recordings were taken during clenching, chewing and protrusion of the lower jaw against a defined force. Comparison with preoperative EMGs proved postsurgical distribution of excitation in class 11 patients to approximate the excitation pattern of eugnathic patients. By contrast, correction in class III malocclusions produced a shift in excitation maxima in the sense of a cranial advance. Harmonization, as evident in class II patients, did not occur. The postoperative discords in masseter excitation patterns, as observed after correction of class III anomalies, are indicative of the risk of relapse and the prolonged phase of retention associated with these conditions.

  18. Fiber-type differences in masseter muscle associated with different facial morphologies

    Science.gov (United States)

    Rowlerson, Anthea; Raoul, Gwénaël; Daniel, Yousif; Close, John; Maurage, Claude-Alain; Ferri, Joel; Sciote, James J.

    2013-01-01

    Background The influence of muscle forces and associated physiologic behaviors on dental and skeletal development is well recognized but difficult to quantify because of the limited understanding of the interrelationships between physiologic and other mechanisms during growth. Methods The purpose of this study was to characterize fiber-type composition of masseter muscle in 44 subjects during surgical correction of malocclusion. Four fiber types were identified after immunostaining of biopsy sections with myosin heavy chain-specific antibodies, and the average fiber diameter and percentage of muscle occupancy of the fiber types were determined in each of 6 subject groups (Class II or Class III and open bite, normal bite, or deepbite). A 2 × 3 × 4 analysis of variance was used to determine significant differences between mean areas for fiber types, vertical relationships, and sagittal relationships. Results There were significant differences in percentage of occupancy of fiber types in masseter muscle in bite groups with different vertical dimensions. Type I fiber occupancy increased in open bites, and conversely, type II fiber occupancy increased in deepbites. The association between sagittal jaw relationships and mean fiber area was less strong, but, in the Class III group, the average fiber area was significantly different between the open bite, normal bite, and deepbite subjects. In the Class III subjects, type I and I/II hybrid fiber areas were greatly increased in subjects with deepbite. Conclusions Given the variation between subjects in fiber areas and fiber numbers, larger subject populations will be needed to demonstrate more significant associations between sagittal relationships and muscle composition. However, the robust influence of jaw-closing muscles on vertical dimension allowed us to conclude that vertical bite characteristics vary according to the fiber type composition of masseter muscle. PMID:15643413

  19. Patterns of experimentally induced pain in pericranial muscles

    DEFF Research Database (Denmark)

    Schmidt-Hansen, Peter Thede; Svensson, Peter; Jensen, Troels Staehelin

    2006-01-01

    Nociceptive mechanisms in the craniofacial muscle tissue are poorly understood. The pain pattern in individual pericranial muscles has not been described before. Experimental muscle pain was induced by standardized infusions of 0.2 ml 1 m hypertonic saline into six craniofacial muscles (masseter....... cervically innervated dermatomes (P pain patterns and pain sensitivity in different craniofacial muscles in healthy volunteers, which may be of importance for further research on different craniofacial pain conditions......., anterior temporalis, posterior temporalis, trapezius, splenius capitis and sternocleidomastoid) in 20 healthy subjects. The pressure pain thresholds (PPTs) were determined before and after infusions. The subjects continuously reported intensity of saline-induced pain on an electronic visual analogue scale...

  20. The influence of the type of contraction on the masseter muscle EMG power spectrum.

    Science.gov (United States)

    Nadeau, S; Bilodeau, M; Delisle, A; Chmielewski, W; Arsenault, A B; Gravel, D

    1993-01-01

    Different behaviours of the EMG power spectrum across increasing force levels have been reported for the masseter muscle. A factor that could explain these different behaviours may be the type of contraction used, as was recently shown for certain upper limb muscles(5). The purpose of this study was to compare, between two types of isometric contractions, the behaviour of EMG power spectrum statistics (median frequency (MF) and mean power frequency (MPF)) obtained across increasing force levels. Ten women exerted, while biting in the intercuspal position, three 5 s ramp contractions that increased linearly from 0 to 100% of the maximal voluntary contraction (MVC). They also completed three step contractions (constant EMG amplitude) at each of the following levels: 20, 40, 60 and 80% MVC. EMG signals from the masseter muscle were recorded with miniature surface electrodes. The RMS, as well as the MPF and MF of the power spectrum were calculated at 20, 40, 60 and 80% MVC for each type of contraction. As expected, the RMS values showed similar increases with increasing levels of effort for both types of contractions. Different behaviours for both MPF (contraction(∗)force interaction, ANOVA, P0.05) across increasing levels of effort were found between the two types of contraction. The use of step contractions gave rise to a decrease of both MPF and MF with increasing force, while the use of ramp contractions gave rise to an increase in both statistics up to at least 40% MVC followed by a decrease at higher force levels. These findings suggest that the type of contraction used does influence the behaviour of the spectral statistics across increasing force levels and that this could explain the differences obtained in previous studies for the masseter muscle. Copyright © 1993. Published by Elsevier Ltd.

  1. Initial Presentation of Renal Cell Carcinoma as a Metastatic Mass within the Masseter Muscle: A Case Report and Literature Review

    Energy Technology Data Exchange (ETDEWEB)

    Bae, Kyung Eun; Lee, Han Bee; Cho, Woo Ho; Kim, Jae Hyung; Lee, Ji Hae; Kang, Min Jin [Dept. of Radiology, Sanggye Paik Hospital, Inje University College of Medicine, Seoul (Korea, Republic of); Kim, Hyun Jung [Dept. of Pathology, Sanggye Paik Hospital, Inje University College of Medicine, Seoul (Korea, Republic of)

    2012-02-15

    Renal cell carcinoma (RCC) is often concomitant with distant metastasis, and these metastases are the first sign of an otherwise occult primary. Whereas metastasis of RCC to the head and neck has been reported, metastasis to the masseter muscle, which is composed of skeletal muscle, is quite rare. We now report the case of a 66-year-old man who had a past history of pulmonary tuberculosis, with RCC metastasis of a well-defined intensely enhancing hypervascular mass in the masseter muscle as the initial presentation. We present the imaging findings of this case and a literature review about radiologic differential diagnosis of intramasseteric masses.

  2. Chronic sleep deprivation alters the myosin heavy chain isoforms in the masseter muscle in rats.

    Science.gov (United States)

    Cao, Ruihua; Huang, Fei; Wang, Peihuan; Chen, Chen; Zhu, Guoxiong; Chen, Lei; Wu, Gaoyi

    2015-05-01

    To investigate the changes in myosin heavy chain (MyHC) isoforms of rat masseter muscle fibres caused by chronic sleep deprivation and a possible link with the pathogenesis of disorders of the temporomandibular joint (TMJ). A total of 180 male rats were randomly divided into three groups (n=60 in each): cage controls, large platform controls, and chronic sleep deprivation group. Each group was further divided into three subgroups with different observation periods (7, 14, and 21 days). We investigated he expression of MyHC isoforms in masseter muscle fibres by real-time quantitative polymerase chain reaction (PCR), Western blotting, and immunohistochemical staining. In rats with chronic sleep deprivation there was increased MyHC-I expression in layers of both shallow and deep muscles at 7 and 21 days compared with the control groups, whereas sleep deprivation was associated with significantly decreased MyHC-II expression. At 21 days, there were no differences in MyHC-I or MyHC-II expression between the groups and there were no differences between the two control groups at any time point. These findings suggest that chronic sleep deprivation alters the expression of MyHC isoforms, which may contribute to the pathogenesis of disorders of the TMJ.

  3. Evaluation of the masseter muscle elasticity with the use of acoustic coupling agents as references in strain sonoelastography.

    Science.gov (United States)

    Nakayama, M; Ariji, Y; Nishiyama, W; Ariji, E

    2015-01-01

    To verify the use of a single coupling agent as a reference to obtain the elasticity index (EI) ratios and to investigate the EI ratios of the masseter muscles of healthy volunteers. Muscle phantoms with known elasticity (20, 40 and 60 kPa in the Young's modulus) were examined by strain-type sonoelastography using a coupling agent as the reference. Eight examiners tested soft (with 7 kPa) and hard (with 40 kpa) reference coupling agents separately. The correlation coefficients were determined between the EI ratio and Young's modulus of muscle phantoms. The interclass correlation coefficients were calculated for inter- and intraexaminer agreement. Strong correlations were found between the EI ratios and Young's modulus for both soft and hard references. The variations of the EI ratios were larger with soft coupling agents than those with hard coupling agents, and they increased in phantoms with 60 kPa elasticity. There were no differences in the EI ratios of the masseter muscle at rest between males and females or between the right and left sides. The ratio increased during clenching. The hard reference coupling agent was suitable for obtaining EI ratio of the masseter muscle. No differences were found in the EI ratios of the masseter muscle either between sexes or between the right and left sides at rest, and the ratios increased with the widening of their variations during clenching.

  4. EMG power spectrum and motor unit characteristics in the masseter muscle of the rabbit.

    Science.gov (United States)

    Turkawski, S J; van Eijden, T M

    2000-04-01

    Masticatory muscles contain a large variety of motor units with different physiological and morphological properties. In this study, we tested the hypothesis that a relationship exists between the mechanical and myo-electric properties of single motor units in the masseter muscle of the rabbit. It was expected that faster-contracting motor units, which usually have a relatively large number of fibers with large diameters, should have faster action potentials with larger amplitudes than slower motor units. Single motor units were stimulated. A two-dimensional force transducer registered mechanical parameters of the units. EMG electrodes were used to determine amplitude and frequency parameters of the action potentials of the same units. The results showed that faster-contracting motor units indeed produced action potentials with higher conduction velocities. However, faster motor units had no significant larger amplitude of the action potential. Small but significant positive correlations were found between the tetanic peak force and the amplitude of the action potentials. Little difference was found among the various frequency and amplitude parameters, respectively, making them equally suitable to describe the action potential. Surprisingly, a negative correlation between the amplitude and frequency parameters of the action potential was found, which may result from variability in arrival times of action potentials at the electrode site. Regional differences in the frequency parameters were found between the anterior and posterior parts of the superficial masseter.

  5. [Motor unit activities of human masseter muscle during sustained voluntary contractions].

    Science.gov (United States)

    Shimizu, T

    1990-02-01

    The purpose of this paper is to investigate the motor unit activities of the human masseter muscle during sustained the bite force at a constant level. The electrical activities recorded with surface and inserted electrodes were studied, with the following results. 1. The masseter muscle had the changes of activities in two phases as a contraction progressed. 2. In the first phase, surface EMG activities decreased and discharge frequency of motor units also decreased. 3. In the second phase, surface EMG activities increased and discharge frequency of motor units also increased. 4. In the first phase, it was suggested that the bite force was maintained by an increase in the twitch tension produced by a motor unit and that there were no recruitment of additional motor units. 5. In the second phase, it was indicated that the bite force was maintained by the recruitment of new motor units and an increase in the discharge frequency of motor units to compensate a loss of force resulted from the contractile element fatigue.

  6. [Relationship between jaws and the masseter muscle by superimposing MR images on the cephalogram].

    Science.gov (United States)

    Higashino, Ryoji

    2006-03-01

    The purpose of this study was to observe the morphological relationship between maxillofacial skeleton and masseter by superimposing the masseter image constructed by MR image scanning on the cephalogram. Sixteen subjects with different mandibular plane angle were examined in this study. Cephalogram and MR images of each subject were taken, and the images were input to a computer by using a digitizer. The areas of masseter were selected in each MR scan image which were projected to the mid-sagittal layer of the MR scan images. The synthesized image of cephalogram and masseter was obtained by completely superimposing sagittal images of the masseter with the mid-sagittal-plane MR image on the cephalogram. The inclination of masseter was determined by the center of gravity on the cross-section of masseter. These synthesized images of cephalogram and masseter showed various shapes of masseter according to different mandibular plane angle. The inclination of masseter had a close correlation with some skeletal parameters (mandibular plane angle, ANB, Y-axis, facial angle, saddle angle) of cephalometric analysis. The volume of the masseter also had a close correlation with skeletal parameters (mandibular plane angle, gonial angle, Y-axis). These results revealed that morphometric analysis using synthesized images of cephalogram and masseter is useful, and that the inclination and the volume of masseter may have an influence on the shape of the mandibular bone and its vertical and anteroposterior development.

  7. MRS assessment of glutamate clearance in a novel masticatory muscle pain model.

    NARCIS (Netherlands)

    Gambarota, G.; Philippens, M.E.P.; Cairns, B.E.; Dong, X.D.; Renema, W.K.J.; Heerschap, A.

    2005-01-01

    The injection of 1.0 M glutamate into the masseter (jaw-closer) muscle results in a short period of muscle pain (5-10 min) and a prolonged period of mechanical sensitization (> 30 min). It is unclear, however, whether there is a temporal relationship between intramuscular glutamate concentration and

  8. Sarcoglycan complex in masseter and sternocleidomastoid muscles of baboons: an immunohistochemical study

    Directory of Open Access Journals (Sweden)

    G. Cutroneo

    2015-06-01

    Full Text Available The sarcoglycan complex consists of a group of single-pass transmembrane glycoproteins that are essential to maintain the integrity of muscle membranes. Any mutation in each sarcoglycan gene causes a series of recessive autosomal dystrophin-positive muscular dystrophies. Negative fibres for sarcoglycans have never been found in healthy humans and animals. In this study, we have investigated whether the social ranking has an influence on the expression of sarcoglycans in the skeletal muscles of healthy baboons. Biopsies of masseter and sternocleidomastoid muscles were processed for confocal immunohistochemical detection of sarcoglycans. Our findings showed that baboons from different social rankings exhibited different sarcoglycan expression profiles. While in dominant baboons almost all muscles were stained for sarcoglycans, only 55% of muscle fibres showed a significant staining. This different expression pattern is likely to be due to the living conditions of these primates. Sarcoglycans which play a key role in muscle activity by controlling contractile forces may influence the phenotype of muscle fibres, thus determining an adaptation to functional conditions. We hypothesize that this intraspecies variation reflects an epigenetic modification of the muscular protein network that allows baboons to adapt progressively to a different social status.

  9. Sarcoglycan complex in masseter and sternocleidomastoid muscles of baboons: an immunohistochemical study.

    Science.gov (United States)

    Cutroneo, G; Centofanti, A; Speciale, F; Rizzo, G; Favaloro, A; Santoro, G; Bruschetta, D; Milardi, D; Micali, A; Di Mauro, D; Vermiglio, G; Anastasi, G; Trimarchi, F

    2015-06-05

    The sarcoglycan complex consists of a group of single-pass transmembrane glycoproteins that are essential to maintain the integrity of muscle membranes. Any mutation in each sarcoglycan gene causes a series of recessive autosomal dystrophin-positive muscular dystrophies. Negative fibres for sarcoglycans have never been found in healthy humans and animals. In this study, we have investigated whether the social ranking has an influence on the expression of sarcoglycans in the skeletal muscles of healthy baboons. Biopsies of masseter and sternocleidomastoid muscles were processed for confocal immunohistochemical detection of sarcoglycans. Our findings showed that baboons from different social rankings exhibited different sarcoglycan expression profiles. While in dominant baboons almost all muscles were stained for sarcoglycans, only 55% of muscle fibres showed a significant staining. This different expression pattern is likely to be due to the living conditions of these primates. Sarcoglycans which play a key role in muscle activity by controlling contractile forces may influence the phenotype of muscle fibres, thus determining an adaptation to functional conditions. We hypothesize that this intraspecies variation reflects an epigenetic modification of the muscular protein network that allows baboons to adapt progressively to a different social status.

  10. Body position effects on EMG activity of sternocleidomastoid and masseter muscles in patients with myogenic cranio-cervical-mandibular dysfunction.

    Science.gov (United States)

    Palazzi, C; Miralles, R; Soto, M A; Santander, H; Zuñiga, C; Moya, H

    1996-07-01

    This study was conducted in order to determine the effects of body position on integrated electromyographic (IEMG) activity of sternocleidomastoid and masseter muscles in 17 patients with myogenic cranio-cervical-mandibular dysfunction. EMG recordings at rest and during swallowing of saliva and maximal voluntary clenching were performed by placing surface electrodes on the sternocleidomastoid and masseter muscles (contralateral to the habitual side of sleeping of each patient), in the following body positions: standing, seated, supine, and lateral decubitus position. Significant higher EMG activities were recorded in the sternocleidomastoid muscle in the lateral decubitus position and in the supine position (except during swallowing), whereas a significant higher EMG activity was recorded in the masseter muscle during maximal voluntary clenching in standing and seated positions. The EMG pattern observed suggests that the presence of parafunctional habits and body position could be closely correlated with the clinical symptomatology in the sternocleidomastoid and masseter muscles at wakening and during waking hours, respectively, in patients with myogenic cranio-cervical-mandibular dysfunction.

  11. Muscle response to the twin-block appliance: an electromyographic study of the masseter and anterior temporal muscles.

    Science.gov (United States)

    Aggarwal, P; Kharbanda, O P; Mathur, R; Duggal, R; Parkash, H

    1999-10-01

    An electromyographic study was performed on 10 young growing girls in the age group of 9 to 12 years with Class II Division 1 malocclusion and retruded mandible, who were under treatment with Twin-block appliances. Bilateral EMG activity of elevator muscles of the mandible (ie, anterior temporalis and masseter) was monitored longitudinally with bipolar surface electrodes to determine changes in postural, swallowing, and maximal voluntary clenching activity during an observation period of 6 months. The changes were noted at the start of treatment (0 month), within 1 month of Twin-block insertion, at the end of 3 months, and at the end of 6 months. The results revealed a significant increase in postural and maximal clenching EMG activity in masseter (P <.01) and a numeric increase in anterior temporalis activity during the 6 month period of treatment. The increased electromyographic activity can be attributed to an enhanced stretch (myotatic) reflex of the elevator muscles, contributing to isometric contractions. The main force for Twin-block treatment appears to be provided through increased active tension in the stretched muscles (motor unit stimulation) and from initiation of myotatic reflex activity and not through passive tension (viscoelastic properties) of jaw muscles. The results of this study reaffirm the importance of full-time wear for functional appliances to exert their maximum therapeutic effect by way of neuromuscular adaptation.

  12. Persistent orofacial muscle pain: Its synonymous terminology and presentation.

    Science.gov (United States)

    Spierings, Egilius L H; Mulder, Maxim J H L

    2017-09-01

    The purpose of the present paper is to describe the presentation of persistent orofacial muscle pain, also commonly referred to as myofascial temporomandibular disorder. In this practice survey, the authors reviewed the demographic and clinical features of 34 patients who were evaluated and diagnosed personally. The majority of the 34 patients were women (82.4%), and their age at consultation averaged 44.6 ± 12.6 (SD) years. The median pain duration was 4.0 years (range: 0.2-34 years). In 97.1% of patients, the pain occurred daily and continuously, and in 51.9% it was unilateral. Chewing or eating made the pain worse in 50% of the patients, and talking in 29.4%. On examination, tightness of the masseter muscle(s) was present in 58.8%, and tenderness in 58.8%. Persistent orofacial muscle pain mostly affects women, generally occurs daily and continuously, and is equally often unilateral and bilateral. Chewing, eating, and talking are the most common aggravating factors, and tightness or tenderness of the masseter muscle(s) is often found on examination.

  13. [Myofascial pain syndrome--fascial muscle pain].

    Science.gov (United States)

    Partanen, Juhani; Ojala, Tuula; Arokoski, Jari P A

    2010-01-01

    Symptoms of myofascial pain syndrome, i.e. fascial muscle pain may occur in several areas of the body, particularly in the neck-shoulder region. The muscle pain symptom in the neck-shoulder region is commonly termed tension neck pain or nonspecific neck pain, but myofascial pain syndrome can also be distinguished into its own diagnosis. This review deals with the clinical picture of myofascial pain syndrome along with pathophysiological hypotheses and treatment options.

  14. Positional changes of the masseter and medial pterygoid muscles after surgical mandibular advancement procedures: an MRI study

    NARCIS (Netherlands)

    Dicker, G.J.; Koolstra, J.H.; Castelijns, J.A.; van Schijndel, R.A.; Tuinzing, D.B.

    2012-01-01

    This study evaluated whether surgical mandibular advancement procedures induced a change in the direction and the moment arms of the masseter (MAS) and medial pterygoid (MPM) muscles. Sixteen adults participated in this study. The sample was divided in two groups: Group I (n = 8) with a mandibular

  15. Effects of the unilateral removal and dissection of the masseter muscle on the facial growth of young rats

    Directory of Open Access Journals (Sweden)

    Lucimar Rodrigues

    2009-03-01

    Full Text Available This study analyzed the effects of the unilateral removal and dissection of the masseter muscle on the facial growth of young rats. A total of 30 one-month-old Wistar rats were used. Unilateral complete removal of the masseter muscle was performed in the removal group, and detachment followed by repositioning of the masseter muscle was performed in the dissection group, while only surgical access was performed in the sham-operated group. The animals were sacrificed at three months of age. Axial radiographic projections of the skulls and lateral projections of the hemimandibles were taken. Cephalometric evaluations were made and the values obtained were submitted to statistical analyses. In the removal group, there were contour alterations of the angular process, and a significant homolateral difference in the length of the maxilla and a significant bilateral difference in the height of the mandibular body and the length of the mandible were observed. Comparison among groups revealed significance only in the removal group. It was concluded that the experimental removal of the masseter muscle during the growing period in rats induced atrophic changes in the angular process, as well as asymmetry of the maxilla and shortening of the whole mandible.

  16. EMG Activity of Masseter Muscles in the Elderly According to Rheological Properties of Solid Food.

    Science.gov (United States)

    Kang, Au Jin; Kim, Don-Kyu; Kang, Si Hyun; Seo, Kyung Mook; Park, Hyoung Su; Park, Ki-Hwan

    2016-06-01

    To assess the impact of aging on masticatory muscle function according to changes in hardness of solid food. Each of fifteen healthy elderly and young people were selected. Subjects were asked to consume cooked rice, which was processed using the guidelines of the Universal Design Foods concept for elderly people (Japan Care Food Conference 2012). The properties of each cooked rice were categorized as grade 1, 2, 3 and 4 (5×10(3), 2×10(4), 5×10(4), and 5×10(5) N/m(2)) respectively. Surface electromyography (sEMG) was used to measure masseter activity from food ingestion to swallowing of test foods. The raw data was normalized by the ratio of sEMG activity to maximal voluntary contraction and compared among subjects. The data was divided according to each sequence of mastication and then calculated within the parameters of EMG activities. Intraoral tongue pressure was significantly higher in the young than in the elderly (psEMG data of the masseter can provide valuable information to aid in the selection of foods according to hardness for the elderly. The results also support the necessity of specialized food preparation or products for the elderly.

  17. Reproducibility of surface EMG in the human masseter and anterior temporalis muscle areas.

    Science.gov (United States)

    Castroflorio, Tommaso; Icardi, Katia; Torsello, Ferruccio; Deregibus, Andrea; Debernardi, Cesare; Bracco, Pietro

    2005-04-01

    The aim of this study was to test the hypothesis that surface electromyography (sEMG) recordings, made at mandibular rest position from the masseter and temporalis anterior areas, are intra- and inter-session reproducible. A template was designed and built to permit the correct electrode placement from one session to the next session. A sample of 18 subjects was examined. Two groups, homogeneous for age, sex, and craniofacial morphology were selected. The first group included asymptomatic subjects with no signs or symptoms of temporomandibular joint dysfunction (TMD) and the second group included patients suffering from muscle-related TMD. Data were obtained from different sEMG recordings made at mandibular rest position in the same session and in different sessions, repositioning the electrodes using a template designed for that purpose. The electromyograph used in this, study is part of the EMG K6-I Win Diagnostic System. Results showed that reproducibility of sEMG signals from the masseter and anterior temporalis areas at mandibular rest position is possible.

  18. Electromyographic analysis of the masseter and temporal muscles in oralized deaf individuals.

    Science.gov (United States)

    Regalo, S C H; Vitti, M; Semprini, M; Rosa, L B; Martinez, F H R M; Santos, C M; Hallak, J E C

    2006-01-01

    Deaf individuals show a number of difficulties related to the functionality of the stomatognathic system, mainly by reason of the little or no use of facial musculature during speech either due to the use of sign language or to the difficulty that these individuals have in articulating words. The stomatognathic system muscles play important roles in functions such as mastication, deglutition, and phonation. This study aimed to assess, by means of computerized bilateral electromyography (EMG), masseter and temporal muscles of 12 oralized deaf individuals in clinical activities that involve part of this masticatory musculature and compare this system's functionality with that of 12 normal listening individuals, performing the same activities. An 8-channel K6-I EMG Light Channel Surface Electromyography device was used (Myo-Tronics Co.Seattle, WA, USA), in addition to disposable double electrodes covered with silver chloride (Duotrodes; Myo-tronics Co., Seattle, WA) containing a conductor gel (Myogel- Myo-tronics Co., Seatlle, WA). The averaged rectified EMG values were normalized with reference to the EMG amplitude induced by a maximum bite force. The statistical analysis confirmed that there were any significant differences between the groups, clinical activities, and muscles, and also effects of interaction among them. The analysis made use of Variance Analysis (ANOVA). Significant differences (p masseter and temporal muscular activity such as mastication, mouth opening and closing, and dental compression. Greater electromyographic values were found for both deaf individuals and healthy controls during clinical activities of mastication and dental compression. Based on the obtained data, we concluded that deaf individuals showed a lower activity of the masticatory musculature than healthy individuals; the differences were significant at the level of p < 0.01 between the performed clinical activities; and all deaf individuals and healthy controls showed greater

  19. Three-dimensional CT might be a potential evaluation modality in correction of asymmetrical masseter muscle hypertrophy by botulinum toxin injection.

    Science.gov (United States)

    No, Yeon A; Ahn, Byeong Heon; Kim, Beom Joon; Kim, Myeung Nam; Hong, Chang Kwon

    2016-01-01

    For correction of this asymmetrical hypertrophy, botulinum toxin type A (BTxA) injection is one of convenient treatment modalities. Unfortunately, physical examination of masseter muscle is not enough to estimate the exact volume of muscle hypertrophy difference. Two Koreans, male and female, of bilateral masseter hypertrophy with asymmetricity were evaluated. BTxA (NABOTA(®), Daewoong, Co. Ltd., Seoul, Korea) was injected at master muscle site with total 50 U (25 U at each side) and volume change was evaluated with three-dimensional (3D) CT image analysis. Maximum reduction of masseter hypertrophy was recognized at 2-month follow-up and reduced muscle size started to restore after 3 months. Mean reduction of masseter muscle volume was 36% compared with baseline. More hypertrophied side of masseter muscle presented 42% of volume reduction at 2-month follow-up but less hypertrophied side of masseter muscle showed 30% of volume shrinkage. In conclusion, 3D CT image analysis might be the exact evaluation tool for correction of asymmetrical masseter hypertrophy by botulinum toxin injection.

  20. Frequency analyses of EMG power spectra of anterior temporal and masseter muscles in children and adults.

    Science.gov (United States)

    Takarada, T; Larrinaga, G A; Nishida, F; Nishino, M

    1990-01-01

    To study the functional change of masticatory muscles during growth and development, frequency analyses of surface electromyogram (EMG) power spectra were carried out. The subjects were six children (five males and one female), aged 4.5 +/- 0.2 years, having full deciduous dentition (Hellman's dental age IIA) and six adults (four males and two females), aged 27.7 +/- 3.8 years, having full permanent dentition. EMG signals were recorded bilaterally by using bipolar silver-surface electrodes from the anterior temporal and masseter muscles while the subjects were chewing gum and while performing maximum clenching in the intercuspal position. A fast Fourier transform algorithm was used to obtain the power-spectral density function and the power spectra of the EMG signals. Since the total power value from 62.5 to 1000 Hz was 100 percent, the frequencies at 25, 50, 75, and 90 percent of the cumulative power were calculated. The results showed that the frequencies at every percent of the cumulative power were age-dependent and that the EMG power spectra patterns in adult muscles were shifted to significantly lower frequencies than those in child muscles. The shift was probably caused by differences in the proportion of fiber type and fiber size between muscles of children and adults.

  1. Effect of experimental jaw muscle pain on EMG activity and bite force distribution at different level of clenching.

    Science.gov (United States)

    Shimada, A; Hara, S; Svensson, P

    2013-11-01

    Bite force at different levels of clenching and the corresponding electromyographic (EMG) activity in jaw-closing muscles were recorded in 16 healthy women before, during and after painful stimulation of the left masseter muscle. Experimental pain was induced by infusion of 5·8% hypertonic saline (HS), and 0·9% isotonic saline (IS) was infused as a control. EMG activity was recorded bilaterally from the masseter and temporalis muscles, and static bite force was assessed by pressure-sensitive films (Dental Pre-scale) at 5, 50 and 100% of maximal voluntary contraction (MVC) during each session. Visual feedback was applied by showing EMG activity to help the subject perform clenching at 5, 50 and 100% MVC, respectively. EMG activity at 100% MVC in left and right masseter decreased significantly during painful HS infusion (1·7-44·6%; P MVC was decreased during HS infusion in the painful masseter muscle (4·8-18·6%; P MVC during HS infusion and in the post-infusion condition (P MVC. In conclusion, experimental pain in the masseter muscle has an inhibitory effect on jaw muscle activity at maximal voluntary contraction, and compensatory mechanisms may influence the recruitment pattern at submaximal efforts.

  2. The role of masseter muscle EMG during DISE to predict the effectiveness of MAD: preliminary results.

    Science.gov (United States)

    Marchese, M R; Scarano, E; Rizzotto, G; Grippaudo, C; Paludetti, G

    2016-12-01

    The use of a mandibular advancement device (MAD) increases the activity of the temporo-mandibular (TM) complex and masseter (MM) muscles with the risk of reducing treatment compliance. Predictors of treatment outcome are of importance in selecting patients who might benefit from MAD without side effects. The role of mandibular advancement (MA) during drug-induced sleep endoscopy (DISE) is controversial. In three cases (BMI DISE. At follow-up all cases improved the AHI, two cases that showed transient increase of MM activity did not suffer from changes of overjet and did not complain of discomfort with the use of MAD. The case that showed a continuing increase of MM activity reported TM discomfort without changes of dental occlusion. EMG of MM during DISE may contribute to ameliorate the selection of cases amenable to treatment with MAD.

  3. A method for studying jaw muscle activity during standardized jaw movements under experimental jaw muscle pain.

    Science.gov (United States)

    Sae-Lee, Daraporn; Wanigaratne, Kamal; Whittle, Terry; Peck, Christopher C; Murray, Greg M

    2006-10-30

    This paper describes a method for studying superficial and deep jaw muscle activity during standardized jaw movements under experimental jaw muscle pain. In 22 healthy adults, pain was elicited in the right masseter muscle via tonic infusion of 4.5% hypertonic saline and which resulted in scores of 30-60 mm on a 100-mm visual analogue scale. Subjects performed tasks in five sessions in a repeated measures design, i.e., control 1, test 1 (during hypertonic or isotonic saline infusion), control 2 (without infusion), test 2 (during isotonic or hypertonic saline infusion), control 3 (without infusion). During each session, subjects performed maximal clenching and standardized jaw tasks, i.e., protrusion, lateral excursion, open/close, chewing. Mandibular movement was recorded with a 6-degree-of-freedom tracking system simultaneously with electromyographic (EMG) activity from the inferior head of the lateral pterygoid muscle with fine-wire electrodes (verified by computer tomography), and from posterior temporalis, the submandibular muscle group and bilateral masseter muscles with surface electrodes. EMG root mean square values were calculated at each 0.5 mm increment of mandibular incisor movement for all tasks under each experimental session. This establishes an experimental model for testing the effects of pain on jaw muscle activity where the jaw motor system is required to perform goal-directed tasks, and therefore should extend our understanding of the effects of pain on the jaw motor system.

  4. Masseter muscle tension, chewing ability, and selected parameters of physical fitness in elderly care home residents in Lodz, Poland

    Directory of Open Access Journals (Sweden)

    Gaszynska E

    2014-07-01

    Full Text Available Ewelina Gaszynska,1 Malgorzata Godala,2 Franciszek Szatko,1 Tomasz Gaszynski3 1Department of Hygiene and Health Promotion, Medical University of Lodz, Poland; 2Department of Nutrition and Epidemiology, Medical University of Lodz, Poland; 3Department of Emergency Medicine and Disaster Medicine, Medical University of Lodz, Poland Background: Maintaining good physical fitness and oral function in old age is an important element of good quality of life. Disability-related impairment of oral function contributes to a deterioration of the diet of older people and to the reduction of their social activity.Objectives: Investigate the association between masseter muscle tension, dental status, and physical fitness parameters.Materials and methods: Two hundred fifty-nine elderly care home residents (97 men, 162 women; mean age, 75.3±8.9 years were involved in this cross-sectional study. Their chewing ability was evaluated by masseter muscle tension palpation, differences of masseter muscle thickness, self-reported chewing ability, number of present and functional teeth, and number of posterior tooth pairs. Masseter muscle thickness was measured by ultrasonography. To assess physical fitness, hand grip strength and the timed up-and-go test were performed. Nutritional status was assessed using body mass index and body cell mass index (BCMI, calculated on the basis of electrical bioimpedance measurements. Medical records were used to collect information on systemic diseases and the number of prescribed medications. Subjects were also evaluated for their ability to perform ten activities of daily living.Results: Ninety-seven percent of the subjects suffered from systemic diseases. The three most prevalent illnesses were cardiac/circulatory 64.5%, musculoskeletal 37.3%, and endocrine/metabolic/nutritional 29.3%. Of the participants, 1.5% were underweight and more than one third (34.4% were overweight. Malnutrition (BCMI below normal was found in almost

  5. Effect of botulinum toxin type A injection into human masseter muscle on stimulated parotid saliva flow rate.

    Science.gov (United States)

    Kwon, J S; Kim, S T; Jeon, Y M; Choi, J H

    2009-04-01

    Botulinum toxin type A (BTX-A) injection into the masseter muscles is used to treat masseteric hypertrophy. No serious side effects of BTX-A have been reported, but patients sometimes complain of xerostomia. The aim of this study was to evaluate the effect of injecting BTX-A into the masseter for the treatment of masseteric hypertrophy on the flow of saliva from the parotid gland. 34 volunteers enrolled in this study. A total of 25 units of BTX-A was injected into each side bilaterally at two points at the center of the lower third of the masseter muscle. Saliva was collected from the parotid gland over a period of 10 min to determine the flow rate for 18 weeks after injection. The flow rate was calculated by dividing the amount in milliliters by the collection time in minutes. There were no significant changes in the stimulated parotid saliva flow at 4, 8, 12 or 18 weeks compared with the baseline. Within this limited study, it can be concluded that BTX-A injection into the masseter does not cause any significant decrease in the production of saliva from the parotid gland.

  6. EMG-force relationships are influenced by experimental jaw-muscle pain.

    Science.gov (United States)

    Wang, K; Arima, T; Arendt-Nielsen, L; Svensson, P

    2000-05-01

    The bite force at different levels and the corresponding electromyographic (EMG) activity of the masseter and anterior temporalis muscles were recorded in 12 healthy subjects in order to evaluate the modulation of EMG-force curves by a standardized painful stimulus. Hypertonic saline (5%) was infused into the right masseter muscle for up to 15 min to induce pain. The pain intensity was scored continuously by the subjects on a 10-cm visual analogue scale (VAS). Subjects were asked to bite on a force transducer at the maximum voluntary bite force (MVBF). They were then asked to bite at submaximum levels of 12, 25, 37, 50, 67, 75 and 87% of MVBF. The biting was performed in three different positions (right first molar, left first molar and incisor) before, during and after infusion. Hypertonic saline caused moderate pain during infusion (mean VAS +/- s.e.m. = 6.5+/-0.5 cm). Both the MVBF and the maximum EMG activity in the right masseter and the left anterior temporalis muscles were significantly decreased during muscle pain when the subjects bit on the painful side. The EMG-force curves could be fit by linear relationships. The slope of the curve became less steep in the right masseter muscle during and after painful biting in every position. The results suggest that tonic saline-induced jaw-muscle pain is able to modulate the motor unit recruitment pattern of the jaw-closing muscles on the painful side. The main effect of pain in this experiment was an inhibition of static EMG activity.

  7. [INVESTIATION OF ELECTROMYOGRAPHIC ACTIVITY OF TEMPORAL AND MASSETER MUSCLES AFTER ORTHODONTIC TREATMENT OF MALOCCLUSION COMPLICATED BY DENTAL CROWDING].

    Science.gov (United States)

    Dmitrenko, M I

    2014-01-01

    The results of investigation showed that it is necessary to use complex methods of orthodontic treatment in patients with malocclusion complicated by dental crowding. Orthodontic appliance therapy should be accompanied by differentiated massage and mioymnastics to improve functional state of masseter and temporal muscles. It was found that after the treatment electromyographic potential amplitude of temporal muscles is on the average in 1.5 times lower as compared with pretreatment records (P muscles during clenching after the treatment of maxillary and mandibular dental crowding (P muscles functional symmetry. During clenching index MASI(MM) significantly decreased in all groups in comparison with pretreatment indices (P < 0.05).

  8. Comparative anatomic study of mandibular growth in rats after bilateral resections of superficial masseter, posterior temporal, and anterior digastric muscles.

    Science.gov (United States)

    Lifshitz, J

    1976-01-01

    Bilateral resections of the superficial masseter, posterior temporal, and anterior digastric muscles of rats were done to determine their effects on mandibular growth. The macroscopic findings support the functional matrix theory of mandibular growth. The analysis of body weight and the statistical two-way analysis of variance done suggest that malnutrition was the main factor that caused the mandibles of rats in the experimental groups of remain undersized.

  9. The human masseter muscle and its biological correlates: A review of published data pertinent to face prediction.

    Science.gov (United States)

    Stephan, Carl N

    2010-09-10

    The masseter muscle forms a cornerstone of anatomical facial reconstruction (FR) methods, yet it is only scantily described in the FR literature despite relatively intense research focus from other disciplines. This suggests that much more data exists for masseter prediction than that which is currently used in FR. This paper reviews the masseter muscle and finds that highly pertinent anatomical and metric data to be available despite being overlooked in the FR literature. This includes variance and means of the perimeter dimensions, thicknesses, cross-sectional areas, volumes, metrics associated with muscle attachment, and correlations with other biological and craniometric variables (such as sex, age, tooth loss, cranial breadths, facial heights, alveolar thicknesses, and gonial angles). The oversight of these metric data adds to a general pattern seen for other hallmark structures of the face in FR and, taken together, these observations hold major ramifications for longstanding debates of FR accuracy, reliability, and error. Irrespectively, the data reviewed in this manuscript help set an improved basis for quantification of FR techniques. Published by Elsevier Ireland Ltd.

  10. SURFACE ELECTROMYOGRAPHY OF MASSETER AND TEMPORAL MUSCLES WITH USE PERCENTAGE WHILE CHEWING ON CANDIDATES FOR GASTROPLASTY.

    Science.gov (United States)

    Santos, Andréa Cavalcante Dos; Silva, Carlos Antonio Bruno da

    Surface electromyography identifies changes in the electrical potential of the muscles during each contraction. The percentage of use is a way to treat values enabling comparison between groups. To analyze the electrical activity and the percentage of use of masseter and temporal muscles during chewing in candidates for gastric bypass. It was used Surface Electromyography Miotool 200,400 (Miotec (r), Porto Alegre/RS, Brazil) integrated with Miograph 2.0 software, involving patients between 20-40 years old. Were included data on electrical activity simultaneously and in pairs of temporal muscle groups and masseter at rest, maximum intercuspation and during the chewing of food previously classified. Were enrolled 39 patients (59 women), mean age 27.1+/-5.7. The percentage of use focused on temporal muscle, in a range of 11-20, female literacy (n=11; 47.82) on the left side and 15 (65.21) on the right-hand side. In the male, nine (56.25) at left and 12 (75.00) on the right-hand side. In masseter, also in the range of 11 to 20, female literacy (n=10; 43.48) on the left side and 11 (47.83) on the right-hand side. In the male, nine (56.25) at left and eight (50.00) on the right-hand side. 40-50% of the sample showed electrical activity in muscles (masseter and temporal) with variable values, and after processing into percentage value, facilitating the comparison of load of used electrical activity between the group, as well as usage percentage was obtained of muscle fibers 11-20% values involving, representing a range that is considered as a reference to the group studied. The gender was not a variable. A eletromiografia de superfície identifica variações dos potenciais elétricos dos músculos durante cada contração realizada. O percentual de uso é uma forma de tratar valores possibilitando comparação entre grupos. Analisar a atividade elétrica e o percentual de uso dos músculos masséteres e temporais durante a mastigação em candidatos à gastroplastia

  11. The effect of a cholecystokinin agonist on masseter muscle activity in the cat.

    Science.gov (United States)

    Sitthisomwong, P; Weiner, S; Levin, L; Reisman, S; Siegel, A

    2000-10-01

    The CCK(B) agonist, pentagastrin, has been shown to induce anxiety in human subjects. Similarly, in the cat model, pentagastrin facilitates the expression of hypothalamically activated emotional behavior. Because hypothalamically mediated emotional behavior is also accompanied by increased EMG activity in the jaw muscles, these experiments were designed to examine the combined effects of administration of pentagastrin with activation of hypothalamically mediated emotional behavior upon jaw muscle EMG activity. Electrodes were carefully lowered through previously placed guide tubes overlying the hypothalamus until a behavioral site was identified. Following the establishment of a stable threshold current for eliciting an emotional behavioral response, the skin overlying the ipsilateral masseter muscle was shaved and cleaned with alcohol, and surface electrodes were attached. The EMG was recorded, amplified, digitized, and stored in a microcomputer for analysis. Mean power frequencies (MPF) and latencies for behavior were calculated for baseline prior to infusion of all drugs. Following this, the effects of intravenous administration of pentagastrin and the CCK(B) antagonist LY288513 on the MPF were determined. The infusion of the CCK(B) agonist, pentagastrin (0.77, 1.92, and 3.84 microg/kg), decreased MPF in a time-related manner. The effects of pentagastrin 1.92 microg/kg were blocked by the CCK(B) antagonist, LY288513 (6.54 microg/kg). In addition, the infusion of LY288513 alone increased MPF. These results are surprising in that pentagastrin's anxiogenic properties would appear to make it likely to facilitate motor activity, not suppress it.

  12. Illusion caused by vibration of muscle spindles reveals an involvement of muscle spindle inputs in regulating isometric contraction of masseter muscles.

    Science.gov (United States)

    Tsukiboshi, Taisuke; Sato, Hajime; Tanaka, Yuto; Saito, Mitsuru; Toyoda, Hiroki; Morimoto, Toshifumi; Türker, Kemal Sitki; Maeda, Yoshinobu; Kang, Youngnam

    2012-11-01

    Spindle Ia afferents may be differentially involved in voluntary isometric contraction, depending on the pattern of synaptic connections in spindle reflex pathways. We investigated how isometric contraction of masseter muscles is regulated through the activity of their muscle spindles that contain the largest number of intrafusal fibers among skeletal muscle spindles by examining the effects of vibration of muscle spindles on the voluntary isometric contraction. Subjects were instructed to hold the jaw at resting position by counteracting ramp loads applied on lower molar teeth. In response to the increasing-ramp load, the root mean square (RMS) of masseter EMG activity almost linearly increased under no vibration, while displaying a steep linear increase followed by a slower increase under vibration. The regression line of the relationship between the load and RMS was significantly steeper under vibration than under no vibration, suggesting that the subjects overestimated the ramp load and excessively counteracted it as reflected in the emergence of bite pressure. In response to the decreasing-ramp load applied following the increasing one, the RMS hardly decreased under vibration unlike under no vibration, leading to a generation of bite pressure even after the offset of the negative-ramp load until the vibration was ceased. Thus the subjects overestimated the increasing rate of the load while underestimating the decreasing rate of the load, due to the vibration-induced illusion of jaw opening. These observations suggest that spindle Ia/II inputs play crucial roles both in estimating the load and in controlling the isometric contraction of masseter muscles in the jaw-closed position.

  13. Study on the association of ultrasonographic thickness and electromyographic activity of masseter muscle in young females with different vertical craniofacial morphology.

    Science.gov (United States)

    Li, Hai-Tao; Cui, Chuan-Jiang; Lu, Shu-Lai; He, Kai-Yun

    2008-10-01

    To study the relationship between ultrasonographic thickness and EMG activity of the masseter muscle in subjects with different vertical craniofacial morphology. Thirty female students were separated into two groups (14 cases with high-angle, 16 cases with low-angle) based on SN-MP angle, FH-MP angle, and FHI. The thickness of the masseter muscle under relaxed conditions and during maximal clenching was assessed by ultrasonography. EMG activity of the masseter muscle under relaxed conditions and during maximal clenching was recorded with bipolar surface electrodes.All measurements were analyzed with SPSS 11.0 software package. Differences between groups were tested for statistical significance using Student's t test. The relationship between masseter muscle thickness and its EMG activity was estimated by Pearson's correlation coefficient. The thickness of the masseter muscle in the low-angle individuals was significantly greater than that in the high-angle individuals under relaxed conditions (P=0.009) and during maximal clenching (P=0.000). Although there was no significant difference in resting EMG activity between the two groups, the EMG activity of masseter muscle in the low-angle individuals was also significantly higher than that in the high-angle individuals during maximal clenching(P=0.022). Relaxed thickness of masseter muscle was significantly correlated with its mean maximum EMG activity in the low-angle group (r=0.61, P=0.003) and moderately correlated with that in the high-angle group (r=0.38, P=0.023). Similar correlation was found between contracted thickness of masseter muscle and the mean maximum EMG activity, being significantly correlated in the low-angle group (r=0.73, P=0.002) and moderately correlated in the high-angle group(r=0.53, P=0.006). The present findings support the concept that subjects with different vertical craniofacial morphology have different form and function of masseter muscle. The ultrasonographic thickness and EMG activity

  14. Compression-induced hyperaemia in the rabbit masseter muscle: a model to investigate vascular mechano-sensitivity of skeletal muscle.

    Science.gov (United States)

    Turturici, Marco; Roatta, Silvestro

    2013-03-01

    Recent evidence suggests that the mechano-sensitivity of the vascular network may underlie rapid dilatory events in skeletal muscles. Previous investigations have been mostly based either on in vitro or on whole-limb studies, neither preparation allowing one to assess the musculo-vascular specificity under physiological conditions. The aim of this work is to characterize the mechano-sensitivity of an exclusively-muscular vascular bed in vivo. In five anesthetized rabbits, muscle blood flow was continuously monitored in the masseteric artery, bilaterally (n = 10). Hyperaemic responses were evoked by compressive stimuli of different extent (50, 100 and 200 mm Hg) and duration (0.5, 1, 2 and 5 s) exerted by a servo-controlled motor on the masseter muscle. Peak amplitude of the hyperaemic response ranged from 340 ± 30% of baseline (at 50 mm Hg) to 459 ± 57% (at 200 mm Hg) (P < 0.05), did not depend on stimulus duration and exhibited very good reliability (ICC = 0.98) when reassessed at 30 min intervals. The time course of the response depended neither on applied pressure nor on the duration of the stimulus. In conclusion, for its high sensitivity and reliability this technique is adequate to characterize mechano-vascular reactivity and may prove useful in the investigation of the underlying mechanisms, with implications in the control of vascular tone and blood pressure in health and disease.

  15. Noninvasive estimation of the location of the end plate in the human masseter muscle using surface electromyograms with an electrode array.

    Science.gov (United States)

    Iwasaki, S; Tokunaga, T; Baba, S; Tanaka, M; Kawazoe, T

    1990-10-01

    The purpose of this study was to estimate the location of the end plate in the masseter muscle, and to decide the appropriate position of surface electrodes for recording electromyograms (EMG) in humans. The subjects were 16 males who had no signs or symptoms of muscular disease. Identical electrode arrays were placed on the masseter muscles on each side. Each subject was asked to clench in the intercuspal position at various levels of maximum EMG amplitude. Eleven amplified EMGs were monitored simultaneously using a linear electrode array consisting of 12 stainless steel contacts. Various values were observed in different regions of the masseter muscle for the root mean square rectified EMG during brief isometric contraction. The superior region of the muscle had lower values than the inferior. The end-plate zone, which is in the center of the lower half of the masseter muscle, showed a lower amplitude than other regions. The propagation of motor unit action potentials was also observed. It was concluded that, aside from the end-plate zone, a position within the lower half of the muscle was most suitable for recording the surface EMG of the masseter muscle.

  16. EMG, bite force, and elongation of the masseter muscle under isometric voluntary contractions and variations of vertical dimension.

    Science.gov (United States)

    Manns, A; Miralles, R; Palazzi, C

    1979-12-01

    The relation EMG activity, bite force, and muscular elongation was studied in eight subjects with complete natural dentition during isometric contractions of the masseter muscle, measured from 7 mm to almost maximum jaw opening. EMG was registered with superficial electrodes and bite force with a gnathodynamometer. In series 1, recordings of EMG activity maintaining bite force constant (10 and 20 kg) show that EMG is high when the bite opening is 7 mm, decreases from 15 to 20 mm, and then increases again as jaw opening approaches maximum opening. In series 2, recordings of bite force maintaining EMG constant show that bite force increases up to a certain range of jaw opening (around 15 to 20 mm) and then decreases as we approach maximum jaw opening. Results show that there is for each experimental subject a physiologically optimum muscular elongation of major efficiency where the masseter develops highest muscular force with least EMG activity.

  17. Experimental muscle pain produces central modulation of proprioceptive signals arising from jaw muscle spindles.

    Science.gov (United States)

    Capra, N F; Ro, J Y

    2000-05-01

    The aim of the present study was to investigate the effects of intramuscular injection with hypertonic saline, a well-established experimental model for muscle pain, on central processing of proprioceptive input from jaw muscle spindle afferents. Fifty-seven cells were recorded from the medial edge of the subnucleus interpolaris (Vi) and the adjacent parvicellular reticular formation from 11 adult cats. These cells were characterized as central units receiving jaw muscle spindle input based on their responses to electrical stimulation of the masseter nerve, muscle palpation and jaw stretch. Forty-five cells, which were successfully tested with 5% hypertonic saline, were categorized as either dynamic-static (DS) (n=25) or static (S) (n=20) neurons based on their responses to different speeds and amplitudes of jaw movement. Seventy-six percent of the cells tested with an ipsilateral injection of hypertonic saline showed a significant modulation of mean firing rates (MFRs) during opening and/or holding phases. The most remarkable saline-induced change was a significant reduction of MFR during the hold phase in S units (100%, 18/18 modulated). Sixty-nine percent of the DS units (11/16 modulated) also showed significant changes in MFRs limited to the hold phase. However, in the DS neurons, the MFRs increased in seven units and decreased in four units. Finally, five DS neurons showed significant changes of MFRs during both opening and holding phases. Injections of isotonic saline into the ipsilateral masseter muscle had little effect, but hypertonic saline injections made into the contralateral masseter muscle produced similar results to ipsilateral injections with hypertonic saline. These results unequivocally demonstrate that intramuscular injection with an algesic substance, sufficient to produce muscle pain, produces significant changes in the proprioceptive properties of the jaw movement-related neurons. Potential mechanisms involved in saline-induced changes in the

  18. Effects of chronic Akt/mTOR inhibition by rapamycin on mechanical overload-induced hypertrophy and myosin heavy chain transition in masseter muscle.

    Science.gov (United States)

    Umeki, Daisuke; Ohnuki, Yoshiki; Mototani, Yasumasa; Shiozawa, Kouichi; Fujita, Takayuki; Nakamura, Yoshiki; Saeki, Yasutake; Okumura, Satoshi

    2013-01-01

    To examine the effects of the Akt/mammalian target of rapamycin (mTOR) pathway on masseter muscle hypertrophy and myosin heavy chain (MHC) transition in response to mechanical overload, we analyzed the effects of bite-opening (BO) on the hypertrophy and MHC composition of masseter muscle of BO-rats treated or not treated with rapamycin (RAPA), a selective mTOR inhibitor. The masseter muscle weight in BO-rats was significantly greater than that in controls, and this increase was attenuated by RAPA treatment. Expression of slow-twitch MHC isoforms was significantly increased in BO-rats with/without RAPA treatment, compared with controls, but the magnitude of the increase was much smaller in RAPA-treated BO-rats. Phosphorylation of p44/42 MAPK (ERK1/2), which preserves fast-twitch MHC isoforms in skeletal muscle, was significantly decreased in BO-rats, but the decrease was abrogated by RAPA treatment. Calcineurin signaling is known to be important for masseter muscle hypertrophy and fast-to-slow MHC isoform transition, but expression of known calcineurin activity modulators was unaffected by RAPA treatment. Taken together, these results indicate that the Akt/mTOR pathway is involved in both development of masseter muscle hypertrophy and fast-to-slow MHC isoform transition in response to mechanical overload with inhibition of the ERK1/2 pathway and operates independently of the calcineurin pathway.

  19. Muscle Cramp - A Common Pain

    Science.gov (United States)

    ... Osteopathic Manipulative Treatment Becoming a DO Video Library Muscle Cramp – A Common Pain Page Content Has a muscle ... body’s natural tendency toward self-healing. Causes of Muscle Cramps Muscle cramps can occur anywhere, anytime to anyone. “ ...

  20. [Frequency analysis of the EMG power spectrum of the anterior temporal and masseter muscles in children and adults].

    Science.gov (United States)

    Takarada, T; Alvarado Larrinaga, G; Nishida, F; Nishino, M

    1989-01-01

    For the investigation of the functional change of the masticatory muscles along with growth and development, the frequency analysis of the EMG power spectrum was carried out. The subjects were 6 children (5 males and 1 female) with full deciduous dentition (Hellman's dental age IIA) aged 4.5 +/- 0.2 years and 6 adults (4 males and 2 females) with full permanent dentition aged 27.7 +/- 3.8 years. EMG signals were recorded bilaterally by means of bipolar silver surface electrodes from the anterior temporal and masseter muscles when the subjects were chewing chewing gum or performing maximum clenches in the intercuspal position. A fast Fourier transform (FFT) algorithm was used to obtain the power spectrum of the EMG signal. As the total power value from 62.5 to 1000 Hz was 100 per cent, the mean frequencies at 25, 50, 75 and 90 per cent of the cumulative power were calculated. The results were as follows: 1. The mean frequencies at each ratio of the cumulative power were age-dependent and EMG power spectrum patterns significantly shifted to lower frequencies in the muscles of the adults. 2. No statistically significant differences between the chewing and clenching, the anterior temporal and masseter muscle and the left and right side were observed in each group.

  1. Molecular Motor MYO1C, Acetyltransferase KAT6B and Osteogenetic Transcription Factor RUNX2 Expression in Human Masseter Muscle Contributes to Development of Malocclusion

    Science.gov (United States)

    Desh, Heather; Gray, S Lauren; Horton, Michael J; Raoul, Gwenael; Rowlerson, Anthea M; Ferri, Joel; Vieira, Alexandre R; Sciote, James J

    2014-01-01

    Objective Type I myosins are molecular motors necessary for glucose transport in the cytoplasm and initiation of transcription in the nucleus. Two of these, MYO1H and MYO1C, are paralogs which may be important in the development of malocclusion. The objective of this study was to investigate their gene expression in the masseter muscle of malocclusion subjects. Two functionally related proteins known to contribute to malocclusion were also investigated: KAT6B (a chromatin remodeling epigenetic enzyme which is activated by MYO1C) and RUNX2 (a transcription factor regulating osteogenesis which is activated by KAT6B). Design Masseter muscle samples and malocclusion classifications were obtained from orthognathic surgery subjects. Muscle was sectioned and immunostained to determine fiber type properties. RNA was isolated from the remaining sample to determine expression levels for the four genes by TaqMan® RT-PCR. Fiber type properties, gene expression quantities and malocclusion classification were compared. Results There were very significant associations (P<0.0000001) between MYO1C and KAT6B expressions. There were also significant associations (P<0.005) between RUNX2 expression and masseter muscle type II fiber properties. Very few significant associations were identified between MYO1C and masseter muscle fiber type properties. Conclusions The relationship between MYO1C and KAT6B suggests that the two are interacting in chromatin remodeling for gene expression. This is the nuclear myosin1 (NM1) function of MYO1C. A surprising finding is the relationship between RUNX2 and type II masseter muscle fibers, since RUNX2 expression in mature muscle was previously unknown. Further investigations are necessary to elucidate the role of RUNX2 in adult masseter muscle. PMID:24698832

  2. Jaw muscle pain and its effect on gothic arch tracings.

    Science.gov (United States)

    Obrez, A; Stohler, C S

    1996-04-01

    Perceived changes in occlusion and decreased range of motion are often expressed by patients with masticatory muscle pain. The adverse loading of craniomandibular tissues that results from an inadequate maxillomandibular relationship in combination with the coexisting dysfunction is widely regarded as the cause of pain. This study was designed to test whether pain can cause significant changes in position of the mandible and therefore form the basis for any perceived changes in the maxillomandibular relationship. A second objective was to determine whether pain can cause changes in the mandibular range of motion. Five subjects who rated pain intensity on a visual analog scale were used in a single-blind, randomized, repeated-measures study design. Tonic muscle pain was induced by infusion of 5% hypertonic saline solution into the central portion of the superficial masseter muscle. Isotonic saline solution was used as a control, with subjects blinded to the type of substance given. The effect of pain on the position of the apex of the gothic arch tracing, the direction of the lateral mandibular border movements, and the mandibular range of motion was studied in a horizontal plane with minimal occlusal separation. Pain significantly affected the position of the apex of the gothic arch tracing in anterior (F = 11.46, p = 0.03) and transverse (F = 35.0, p = 0.004) directions. Similarly, pain affected the orientation of the mandibular lateral border movements (F = 12.44, p = 0.02) and their magnitude (F = 14.97, p = 0.01). All pain-induced effects proved to be reversible. The observed effect of pain can explain the perceived change of bite that is frequently noted by patients with orofacial pain. This study provided evidence of an alternative causal relationship between pain and changes in occlusal relationship and questions occlusal therapy as treatment, directed toward the elimination of the underlying cause in patients with masticatory muscle pain.

  3. A COMPARATIVE-STUDY OF ELECTROMYOGRAMS OF THE MASSETER, TEMPORALIS, AND ANTERIOR DIGASTRIC MUSCLES OBTAINED BY SURFACE AND INTRAMUSCULAR ELECTRODES - RAW-EMG

    NARCIS (Netherlands)

    KOOLE, P; DEJONGH, HJ; BOERING, G

    Electromyographic activity was synchronously recorded by surface and intramuscular electrodes in the same muscle. The activity of the left masseter, left temporalis, and both bellies of the anterior digastric muscle was studied by this double registration technique. In rest position no

  4. Muscle-specific integrins in masseter muscle fibers of chimpanzees: an immunohistochemical study.

    Directory of Open Access Journals (Sweden)

    Gianluigi Vaccarino

    2010-05-01

    Full Text Available Most notably, recent comparative genomic analyses strongly indicate that the marked differences between modern human and chimpanzees are likely due more to changes in gene regulation than to modifications of the genes. The most peculiar aspect of hominoid karyotypes is that human have 46 chromosomes whereas gorillas and chimpanzees have 48. Interestingly, human and chimpanzees do share identical inversions on chromosome 7 and 9 that are not evident in the gorilla karyotype. Thus, the general phylogeny suggests that humans and chimpanzees are sister taxa; based on this, it seems that human-chimpanzee sequence similarity is an astonishing 99%. At this purpose, of particular interest is the inactivation of the myosin heavy chain 16 (MYH16 gene, most prominently expressed in the masticatory muscle of mammals. It has been showed that the loss of this gene in humans may have resulted in smaller masticatory muscle and consequential changes to cranio-facial morphology and expansion of the human brain case. Powerful masticatory muscles are found in most primates; contrarily, in both modern and fossil member Homo, these muscles are considerably smaller. The evolving hominid masticatory apparatus shifted towards a pattern of gracilization nearly simultaneously with accelerated encephalization in early Homo. To better comprehend the real role of the MYH16 gene, we studied the primary proteins present in the muscle fibers of humans and non-humans, in order to understand if they really can be influenced by MYH16 gene. At this aim we examined the muscle-specific integrins, alpha 7B and beta 1D-integrins, and their relative fetal isoforms, alpha 7A and beta 1A-integrins, analyzing, by immunohistochemistry, muscle biopsies of two components of a chimpanzee's group in captivity, an alpha male and a non-alpha male subjects; all these integrins participate in vital biological processes such as maintenance of tissue integrity, embryonic development, cell

  5. Isolated asymptomatic masseter muscle metastasis as first sign of metastatic disease in a patient with known melanoma

    DEFF Research Database (Denmark)

    Gjorup, Caroline Asirvatham; Hendel, Helle Westergren; Svane, Inge Marie

    2016-01-01

    A 65-year-old woman diagnosed with a nodular melanoma on the right shoulder had a PET/CT scan 13 months later demonstrating a FDG-avid mass in the left masseter muscle, which was asymptomatic and not clinically evident. Pathologic analysis confirmed metastasis of melanoma. Further subcutaneous......, intramuscular and bone metastases developed and the patient was treated with surgery and immunotherapy. The patient is in complete-remission with no evident metastases seen on PET/CT 2.5 years after treatment with adoptive cell therapy using tumor-infiltrating lymphocytes (TIL therapy). Asymptomatic skeletal...

  6. The Electrical Activity of the Temporal and Masseter Muscles in Patients with TMD and Unilateral Posterior Crossbite

    Directory of Open Access Journals (Sweden)

    Krzysztof Woźniak

    2015-01-01

    Full Text Available The aim of this study was to assess the influence of unilateral posterior crossbite on the electrical activity of the temporal and masseter muscles in patients with subjective symptoms of temporomandibular dysfunctions (TMD. The sample consisted of 50 patients (22 female and 28 male aged 18.4 to 26.3 years (mean 20.84, SD 1.14 with subjective symptoms of TMD and unilateral posterior crossbite malocclusion and 100 patients without subjective symptoms of TMD and malocclusion (54 female and 46 male aged between 18.4 and 28.7 years (mean 21.42, SD 1.06. The anamnestic interviews were conducted according to a three-point anamnestic index of temporomandibular dysfunction (Ai. Electromyographical (EMG recordings were performed using a DAB-Bluetooth Instrument (Zebris Medical GmbH, Germany. Recordings were carried out in the mandibular rest position and during maximum voluntary contraction (MVC. Analysis of the results of the EMG recordings confirmed the influence of unilateral posterior crossbite on variations in spontaneous muscle activity in the mandibular rest position and maximum voluntary contraction. In addition, there was a significant increase in the Asymmetry Index (As and Torque Coefficient (Tc, responsible for a laterodeviating effect on the mandible caused by unbalanced right and left masseter and temporal muscles.

  7. Effects of experimental pain on jaw muscle activity during goal-directed jaw movements in humans.

    Science.gov (United States)

    Sae-Lee, Daraporn; Whittle, Terry; Forte, Anna R C; Peck, Christopher C; Byth, Karen; Sessle, Barry J; Murray, Greg M

    2008-08-01

    To study the effects of masseter muscle pain on jaw muscle electromyographic (EMG) activity during goal-directed tasks. Mandibular movement was tracked and EMG activity was recorded from bilateral masseter, and right posterior temporalis, anterior digastric, and inferior head of lateral pterygoid muscles in 22 asymptomatic subjects at postural jaw position, and during three tasks: (a) protrusion, (b) contralateral (left), (c) open jaw movement. Tasks were performed during three conditions: control (no infusion), test 1 [continuous infusion into right masseter of 4.5% hypertonic saline to achieve 30-60 mm pain intensity on 100-mm visual analog scale (VAS)], and test 2 (isotonic saline infusion; in 16 subjects only); the sequence of hypertonic and isotonic saline was randomized. The average EMG root-mean-square values at 0.5 mm increments of mid-incisor-point displacement were analysed using linear mixed effects model statistics (significance: P jaw displacement. Hypertonic saline infusion had no significant effect on postural EMG activity in any of the recorded jaw muscles. The data suggest that under constrained goal-directed tasks, the pattern of pain-induced changes in jaw muscle EMG activity is not clear cut, but can vary with the task performed, jaw displacement magnitude, and the subject being studied.

  8. Development of an Eletromiograph and Load Cell for the Silent Period Generation and Measurement in Myoelectric Signals of the Masseter and Temporal Muscles

    Directory of Open Access Journals (Sweden)

    Alexandre BALBINOT

    2011-05-01

    Full Text Available This paper presents the development of an experimental system for the Silent Period (SP generation and characterization in the myoelectric signals of the masseter and temporal muscles derived from an impact on the jaw during maximal voluntary contraction. A load cell to monitor the mechanical stimulus intensity responsible for the SP appearance was developed. This load cell was adapted to the mechanic shooter to generate impacts on the jaw, and strain-gages sensors were used for acquiring signals from such impacts. The system consists of a computer, an analog-digital converter, an electromyograph of up to eight channels, a signal conditioner, and a ring-type load cell adapted to a mechanical impact generator called shooter in this work. Surface electrodes were placed on the right masseter, left masseter, right anterior temporal, and left anterior temporal. Individuals were asked to perform the voluntary muscles contraction. The shooter was positioned at a fixed distance of 5 cm from the individual’s jaw and fired to generate the stimulus. The output signal of the load cell was obtained simultaneously with the EMG signals of the masseter and temporal muscles. Incoming data from EMG and load cell were stored in a computer for further processing. This system was tested in three voluntary individuals and the results demonstrated that the system is suitable for this application, so it was able to generate, acquire, and measure the SP of the masseter and temporal myoelectric signals.

  9. Peripheral Receptor Mechanisms Underlying Orofacial Muscle Pain and Hyperalgesia

    Science.gov (United States)

    Saloman, Jami L.

    Musculoskeletal pain conditions, particularly those associated with temporomandibular joint and muscle disorders (TMD) are severely debilitating and affect approximately 12% of the population. Identifying peripheral nociceptive mechanisms underlying mechanical hyperalgesia, a prominent feature of persistent muscle pain, could contribute to the development of new treatment strategies for the management of TMD and other muscle pain conditions. This study provides evidence of functional interactions between ligand-gated channels, P2X3 and TRPV1/TRPA1, in trigeminal sensory neurons, and proposes that these interactions underlie the development of mechanical hyperalgesia. In the masseter muscle, direct P2X3 activation, via the selective agonist αβmeATP, induced a dose- and time-dependent hyperalgesia. Importantly, the αβmeATP-induced hyperalgesia was prevented by pretreatment of the muscle with a TRPV1 antagonist, AMG9810, or the TRPA1 antagonist, AP18. P2X3 was co-expressed with both TRPV1 and TRPA1 in masseter muscle afferents confirming the possibility for intracellular interactions. Moreover, in a subpopulation of P2X3 /TRPV1 positive neurons, capsaicin-induced Ca2+ transients were significantly potentiated following P2X3 activation. Inhibition of Ca2+-dependent kinases, PKC and CaMKII, prevented P2X3-mechanical hyperalgesia whereas blockade of Ca2+-independent PKA did not. Finally, activation of P2X3 induced phosphorylation of serine, but not threonine, residues in TRPV1 in trigeminal sensory neurons. Significant phosphorylation was observed at 15 minutes, the time point at which behavioral hyperalgesia was prominent. Similar data were obtained regarding another nonselective cation channel, the NMDA receptor (NMDAR). Our data propose P2X3 and NMDARs interact with TRPV1 in a facilitatory manner, which could contribute to the peripheral sensitization underlying masseter hyperalgesia. This study offers novel mechanisms by which individual pro-nociceptive ligand

  10. Effect of experimental chewing on masticatory muscle pain onset

    Directory of Open Access Journals (Sweden)

    Paulo César Rodrigues Conti

    2011-02-01

    Full Text Available OBJECTIVES: To evaluate the effect of a chewing exercise on pain intensity and pressure-pain threshold in patients with myofascial pain. METHODS: Twenty-nine consecutive women diagnosed with myofascial pain (MFP according to the Research Diagnostic Criteria comprised the experimental group and 15 healthy age-matched female were used as controls. Subjects were asked to chew a gum stick for 9 min and to stay at rest for another 9 min afterwards. Pain intensity was rated on a visual analog scale (VAS every 3 min. At 0, 9 and 18 min, the pressure-pain threshold (PPT was measured bilaterally on the masseter and the anterior, medium, and posterior temporalis muscles. RESULTS: Patients with myofascial pain reported increase (76% and no change (24% on the pain intensity measured with the VAS. A reduction of the PPT at all muscular sites after the exercise and a non-significant recovery after rest were also observed. CONCLUSION: The following conclusions can be drawn: 1. there are at least two subtypes of patients with myofascial pain that respond differently to experimental chewing; 2. the chewing protocol had an adequate discriminative ability in distinguishing patients with myofascial pain from healthy controls.

  11. Jaw-motor effects of experimental jaw-muscle pain and stress in patients with deep bite and matched control subjects

    DEFF Research Database (Denmark)

    Sonnesen, Liselotte; Svensson, Peter

    2013-01-01

    OBJECTIVE: The effect of experimental jaw-muscle pain and stress on masticatory muscle activity in TMD-patients has been discussed. Furthermore, associations between TMD and deep bite patients have been studied. Accordingly in the present study, comparison of EMG responses at rest, maximal...... clenching, during evoked pain and stress between deep bite patients and controls was investigated. DESIGN: In 30 deep bite patients and in 30 sex-/age-matched controls with neutral occlusion EMG activity was recorded bilaterally from masseter and anterior temporalis muscles before and during evoked pain...... and before and during a stress task. Evoked pain was induced by injections of glutamate into the masseter (local pain) and brachioradialis (remote pain) muscles and resting EMG activity was recorded before and after 1, 2, 3, 4, 5 and 10min. A precision task was used to simulate a stressful condition and EMG...

  12. In-field masticatory muscle activity in subjects with pain-related TMD diagnoses

    Science.gov (United States)

    Khawaja, S.N.; McCall, W.; Dunford, R.; Nickel, J.C.; Iwasaki, L.R.; Crow, H.C.; Gonzalez, Y.

    2015-01-01

    Objectives Pain-related Temporomandibular disorders (TMD) are the most prevalent conditions among TMDs. There is contrasting evidence available for association of pain-related TMD and masticatory muscle activity (MMA). The present investigation assesses the associations between MMA levels of masseter and temporalis muscles during awake and sleep among pain-related TMD diagnostic groups. Setting and Sample Population The department of Oral Diagnostic Sciences, University at Buffalo. Twenty females and 6 males participated in this study. Material & Methods Using the Diagnostic Criteria for Temporomandibular Disorders (DC-TMD), participants were diagnostically categorized. Subjects used a custom monitoring system, which recorded in–field muscle activities. A factorial model tested for association between independent variable (muscle, time period, MMA level, diagnostic group) effects and the logarithm of MMA. Greenhouse–Geisser test was used to determine any statistically significant associations (p ≤ 0.003). Results No statistically significant association was found among four-way, three-way, and two-way analyses. However, among the main effects, range of magnitudes was the only variable to be statistically significant. Although the data suggest a trend of increased masseter MMA in the pain-related TMD diagnoses group both during awake and sleep time periods, such observation is not maintained for the temporalis muscle. In addition, temporalis MMA was found to be higher in the pain-related TMD diagnoses group only at extreme activity levels (TMD conditions. PMID:25865542

  13. [Comparison of postmortal changes in the ultrastructure of the masseter muscle and the longissimus dorsi muscle in pigs with PSE-meat].

    Science.gov (United States)

    Bergmann, V

    1975-01-01

    Samples of the two muscles were taken from 8 Landrace fattened pigs, affected with pale, soft exudative meat, during stunning and 15, 30, 45 and 60 minutes after death; also 2, 3, 6, 12, 24 and 48 hours after slaughter, with storage at 20 degrees C for the first six hours and 2-5 degrees C subsequently. Considerable changes were found during the first hour after death, or even in samples taken during stunning, in longissimus dorsi samples. These consisted of destruction of mitochondria and sarcoplasmic reticulum, breakdown of cell membranes, liberation of clumps of fibre protein, disappearance of glycogen, rigor and destruction of capillaries. Such changes would account for the features of pale, soft exudative meat such as water loss, brief rigor, pale colour, deficiency of energy-rich phosphates. By contrast, in the masseter muscles of the same animal these changes did not occur until later, or were in port absent. In both muscle the breakdown of fibres took place by destruction of the "I" bands and the "Z" strips, and this process also commenced in longissimus dorsi before masseter.

  14. Increased levels of intramuscular cytokines in patients with jaw muscle pain.

    Science.gov (United States)

    Louca Jounger, S; Christidis, N; Svensson, P; List, T; Ernberg, M

    2017-12-01

    The aim of this study was to investigate cytokine levels in the masseter muscle, their response to experimental tooth-clenching and their relation to pain, fatigue and psychological distress in patients with temporomandibular disorders (TMD) myalgia. Forty women, 20 with TMD myalgia (Diagnostic Criteria for TMD) and 20 age-matched healthy controls participated. Intramuscular microdialysis was performed to sample masseter muscle cytokines. After 140 min (baseline), a 20-minute tooth-clenching task was performed (50% of maximal voluntary contraction force). Pain (Numeric rating scale 0-10) and fatigue (Borg's Ratings of Perceived Exertion 6-20) were assessed throughout microdialysis, while pressure-pain thresholds (PPT) were assessed before and after microdialysis. Perceived stress (PSS-10) and Trait Anxiety (STAI) were assessed before microdialysis. The levels of IL-6, IL-7, IL-8 and IL-13 were higher in patients than controls (Mann Whitney U-test; P's tooth-clenching in both groups (Wilcoxon test; P's pain and fatigue than controls before and after tooth-clenching (P pain or fatigue. Also, there were no differences in stress or anxiety levels between groups. In conclusion, the masseter levels of IL-6, IL-7, IL-8 and IL-13 were elevated in patients with TMD myalgia and increased in response to tooth-clenching. Tooth-clenching increased jaw muscle pain and fatigue, but without correlations to cytokine levels. This implies that subclinical muscle inflammation may be involved in TMD myalgia pathophysiology, but that there is no direct cause-relation between inflammation and pain.

  15. Relationship between Occlusal Force Distribution and the Activity of Masseter and Anterior Temporalis Muscles in Asymptomatic Young Adults

    Directory of Open Access Journals (Sweden)

    Aneta Wieczorek

    2013-01-01

    Full Text Available Healthy subjects have a prevalent side on which they display higher-muscle activity during clenching. The relationship between symmetry of masseter muscle (MM and anterior temporalis (TA muscle activities and occlusion has been evaluated on the basis of physiological parameters. The aim of the present study was to investigate whether the symmetry of surface EMG (sEMG activity in asymptomatic young adults is related to symmetry of occlusal contacts. Material. The study population consisted of seventy-two 18-year-old subjects with no temporomandibular disorder (TMD symptoms. Method. All the participants underwent an sEMG recording with an 8-channel electromyograph (BioEMG III. A T-Scan III evolution 7.01 device was used to analyze the occlusal contact points. Results. The correlation between the activity of right (R and left (L TA and the percentage of occlusal contacts was assessed, but no significant differences were found between the RMM and LMM muscles. The differences in the medium values of sEMG between males and females were not statistically significant. Equilibrated muscular activity between RTA and LTA occurred when occlusal contacts reached the percentage of 65% on the left side. Conclusion. The symmetry of sEMG activity in asymptomatic young adults is not related to symmetry of occlusal contacts.

  16. Cysticercosis of masseter

    Directory of Open Access Journals (Sweden)

    B Dilip Kumar

    2011-01-01

    Full Text Available Cysticercosis is a parasitic infestation caused by the larval stage of Taenia solium, a cestodic paratise. It is a common disease in developing countries where it is also endemic. The most commonly infested body organs include subcutaneous tissues, brain and skeletal muscles. It is interesting to note that oral lesion of cysticercosis is a rare event. Here we report an isolated lesion of cysticercosis in the masseter muscle.

  17. Characteristics of referred muscle pain to the head from active trigger points in women with myofascial temporomandibular pain and fibromyalgia syndrome.

    Science.gov (United States)

    Alonso-Blanco, Cristina; Fernández-de-Las-Peñas, César; de-la-Llave-Rincón, Ana Isabel; Zarco-Moreno, Pedro; Galán-Del-Río, Fernando; Svensson, Peter

    2012-11-01

    Our aim was to compare the differences in the prevalence and the anatomical localization of referred pain areas of active trigger points (TrPs) between women with myofascial temporomandibular disorder (TMD) or fibromyalgia (FMS). Twenty women (age 46 ± 8 years) with TMD and 20 (age 48 ± 6 years) with FMS were recruited from specialized clinic. Bilateral temporalis, masseter, sternocleidomastoid, upper trapezius, and suboccipital muscles were examined for TrPs. TrPs were identified by palpation and considered active when the pain reproduced familiar pain symptom experienced by the patient. The referred pain areas were drawn on anatomical maps, digitalized and also measured. A new analysis technique based on a center of gravity (COG) method was used to quantitative estimate of the localization of the TrP referred pain areas. Women with FMS exhibited larger areas of usual pain symptoms than women with myofascial TMD (P pain on the frontal and posterior pain maps were located more superior in TMD than in FMS. The number of active TrPs was significantly higher in TMD (mean ± SD 6 ± 1) than in FMS (4 ± 1) (P = 0.002). Women with TMD exhibited more active TrPs in the temporalis and masseter muscles than FMS (P pain areas than those with TMD for sternocleidomastoid and suboccipital muscles (P pain areas were found in TMD, the referred pain was more pronounced in the orofacial region, whereas the referred pain in FMS was more pronounced in the cervical spine. This study showed that the referred pain elicited from active TrPs shared similar patterns as usual pain symptoms in women with TMD or FMS, but that distinct differences in TrP prevalence and location of the referred pain areas could be observed. Differences in location of referred pain areas may help clinicians to determine the most relevant TrPs for each pain syndrome in spite of overlaps in pain areas.

  18. Role of cyclic AMP sensor Epac1 in masseter muscle hypertrophy and myosin heavy chain transition induced by β2-adrenoceptor stimulation.

    Science.gov (United States)

    Ohnuki, Yoshiki; Umeki, Daisuke; Mototani, Yasumasa; Jin, Huiling; Cai, Wenqian; Shiozawa, Kouichi; Suita, Kenji; Saeki, Yasutake; Fujita, Takayuki; Ishikawa, Yoshihiro; Okumura, Satoshi

    2014-12-15

    The predominant isoform of β-adrenoceptor (β-AR) in skeletal muscle is β2-AR and that in the cardiac muscle is β1-AR. We have reported that Epac1 (exchange protein directly activated by cAMP 1), a new protein kinase A-independent cAMP sensor, does not affect cardiac hypertrophy in response to pressure overload or chronic isoproterenol (isoprenaline) infusion. However, the role of Epac1 in skeletal muscle hypertrophy remains poorly understood. We thus examined the effect of disruption of Epac1, the major Epac isoform in skeletal muscle, on masseter muscle hypertrophy induced by chronic β2-AR stimulation with clenbuterol (CB) in Epac1-null mice (Epac1KO). The masseter muscle weight/tibial length ratio was similar in wild-type (WT) and Epac1KO at baseline and was significantly increased in WT after CB infusion, but this increase was suppressed in Epac1KO. CB treatment significantly increased the proportion of myosin heavy chain (MHC) IIb at the expense of that of MHC IId/x in both WT and Epac1KO, indicating that Epac1 did not mediate the CB-induced MHC isoform transition towards the faster isoform. The mechanism of suppression of CB-mediated hypertrophy in Epac1KO is considered to involve decreased activation of Akt signalling. In addition, CB-induced histone deacetylase 4 (HDAC4) phosphorylation on serine 246 mediated by calmodulin kinase II (CaMKII), which plays a role in skeletal muscle hypertrophy, was suppressed in Epac1KO. Our findings suggest that Epac1 plays a role in β2-AR-mediated masseter muscle hypertrophy, probably through activation of both Akt signalling and CaMKII/HDAC4 signalling. © 2014 The Authors. The Journal of Physiology © 2014 The Physiological Society.

  19. The effect of sensory level electrical stimulation of the masseter muscle in early stroke patients with dysphagia: A randomized controlled study.

    Science.gov (United States)

    Umay, Ebru K; Yaylaci, Atilay; Saylam, Guleser; Gundogdu, Ibrahim; Gurcay, Eda; Akcapinar, Dehen; Kirac, Zeynep

    2017-01-01

    Dysphagia is a serious cause of morbidity and mortality in stroke patients. As the first study in literature, we aimed to evaluate the effects of sensory-level electrical stimulation (SES) to bilateral masseter muscles in early stroke patients with dysphagia. This study was conducted at the Physical Medicine and Rehabilitation Clinic of our hospital between 2013 and 2015. Ninety-eight patients with dysphagia within the first month after ischemic stroke were included in this study. Patients were evaluated by bedside screening tests (Bedside Dysphagia Score, Neurological Examination Dysphagia Score, Total Dysphagia Score, and Mann Assessment of Swallowing Ability test) and by flexible fibreoptic endoscopic evaluation of swallowing (FEES) methods. All patients were included in a traditional swallowing therapy. Patients were divided into two groups, namely the "stimulation group" and "sham group." SES was applied to bilateral masseter muscles. Evaluation parameters were compared between the groups before and after therapy. The Friedman test, Wilcoxon Signed Rank test, Mann-Whitney U test, and Fisher exact test were used in this study. There was a significant improvement in dysphagia severity scores evaluated by bedside screening tests and FEES in cognitive and total functionality levels except in motor functional independence level in the stimulation group. In the sham group, there were no significant changes in the evaluation parameters. SES applied to bilateral masseter muscles may provide an effective treatment for both dysphagia and cognitive function in early stroke patients.

  20. Illusion caused by vibration of muscle spindles reveals an involvement of muscle spindle inputs in regulating isometric contraction of masseter muscles

    National Research Council Canada - National Science Library

    Tsukiboshi, Taisuke; Sato, Hajime; Tanaka, Yuto; Saito, Mitsuru; Toyoda, Hiroki; Morimoto, Toshifumi; Türker, Kemal Sitki; Maeda, Yoshinobu; Kang, Youngnam

    2012-01-01

    .... In response to the increasing-ramp load, the root mean square (RMS) of masseter EMG activity almost linearly increased under no vibration, while displaying a steep linear increase followed by a slower increase under vibration...

  1. The role of TRPA1 in muscle pain and mechanical hypersensitivity under inflammatory conditions in rats.

    Science.gov (United States)

    Asgar, J; Zhang, Y; Saloman, J L; Wang, S; Chung, M-K; Ro, J Y

    2015-12-03

    Transient receptor potential cation channel, subfamily A, member 1 (TRPA1) is expressed in muscle afferents and direct activation of these receptors induces acute mechanical hypersensitivity. However, the functional role of TRPA1 under pathological muscle pain conditions and mechanisms by which TRPA1 mediate muscle pain and hyperalgesia are not clearly understood. Two rodent behavioral models validated to assess craniofacial muscle pain conditions were used to study ATP- and N-Methyl-D-aspartate (NMDA)-induced acute mechanical hypersensitivity and complete Freund's adjuvant (CFA)-induced persistent mechanical hypersensitivity. The rat grimace scale (RGS) was utilized to assess inflammation-induced spontaneous muscle pain. Behavioral pharmacology experiments were performed to assess the effects of AP18, a selective TRPA1 antagonist under these conditions. TRPA1 expression levels in trigeminal ganglia (TG) were examined before and after CFA treatment in the rat masseter muscle. Pre-treatment of the muscle with AP18 dose-dependently blocked the development of acute mechanical hypersensitivity induced by NMDA and α,β-methylene adenosine triphosphate (αβmeATP), a specific agonist for NMDA and P2X3 receptor, respectively. CFA-induced mechanical hypersensitivity and spontaneous muscle pain responses were significantly reversed by post-treatment of the muscle with AP18 when CFA effects were most prominent. CFA-induced myositis was accompanied by significant up-regulation of TRPA1 expression in TG. Our findings showed that TRPA1 in muscle afferents plays an important role in the development of acute mechanical hypersensitivity and in the maintenance of persistent muscle pain and hypersensitivity. Our data suggested that TRPA1 may serve as a downstream target of pro-nociceptive ion channels, such as P2X3 and NMDA receptors in masseter afferents, and that increased TRPA1 expression under inflammatory conditions may contribute to the maintenance of persistent muscle pain

  2. A comparative study of electromyograms of the masseter, temporalis, and anterior digastric muscles obtained by surface and intramuscular electrodes: raw-EMG.

    Science.gov (United States)

    Koole, P; de Jongh, H J; Boering, G

    1991-07-01

    Electromyographic activity was synchronously recorded by surface and intramuscular electrodes in the same muscle. The activity of the left masseter, left temporalis, and both bellies of the anterior digastric muscle was studied by this double registration technique. In rest position no electromyographic activity could be detected in any of the muscles by both techniques. Both techniques give comparable results in cyclic jaw movements. In isometric contractions, however, differences in the registered activity were observed between the surface electrode on the depressor group muscles and the intramuscularly recorded anterior digastric muscles. Silent periods evoked in the elevator muscles were of slightly longer duration when recorded by intramuscular electrodes than when recorded by surface electrodes. A protruded position of the mandible results in a silent period of longer duration than the position of the mandible in maximal occlusion during clenching for both techniques.

  3. Effect of acupuncture depth on muscle pain

    Directory of Open Access Journals (Sweden)

    Kitakoji Hiroshi

    2011-06-01

    Full Text Available Abstract Background While evidence supports efficacy of acupuncture and/or dry needling in treating musculoskeletal pain, it is unclear which needling method is most effective. This study aims to determine the effects of depth of needle penetration on muscle pain. Methods A total of 22 healthy volunteers performed repeated eccentric contractions to induce muscle soreness in their extensor digital muscle. Subjects were assigned randomly to four groups, namely control group, skin group (depth of 3 mm: the extensor digital muscle, muscle group (depth of 10 mm: the extensor digital muscle and non-segmental group (depth of 10 mm: the anterior tibial muscle. Pressure pain threshold and electrical pain threshold of the skin, fascia and muscle were measured at a point 20 mm distal to the maximum tender point on the second day after the exercise. Results Pressure pain thresholds of skin group (depth of 3 mm: the extensor digital muscle and muscle group (depth of 10 mm: the extensor digital muscle were significantly higher than the control group, whereas the electrical pain threshold at fascia of muscle group (depth of 10 mm: the extensor digital muscle was a significantly higher than control group; however, there was no significant difference between the control and other groups. Conclusion The present study shows that acupuncture stimulation of muscle increases the PPT and EPT of fascia. The depth of needle penetration is important for the relief of muscle pain.

  4. Emotional modulation of muscle pain is associated with polymorphisms in the serotonin transporter gene.

    Science.gov (United States)

    Horjales-Araujo, Emilia; Demontis, Ditte; Lund, Ellen Kielland; Vase, Lene; Finnerup, Nanna Brix; Børglum, Anders D; Jensen, Troels Staehelin; Svensson, Peter

    2013-08-01

    The perception of pain is determined by a combination of genetic, neurobiological, cultural, and emotional factors. Recent studies have demonstrated an association between specific genotypes and pain perception. Particular focus has been given to the triallelic polymorphism in the promoter region of the serotonin transporter gene in relation to pain perception. The aim of this study was to investigate whether the modulatory effect of emotions mediated by visual stimuli on muscular pain perception is genotype dependent. A total of 150 healthy subjects were selected on the basis of their polymorphism in the serotonin transporter gene. First, visual conditioning was performed with positive, negative, and neutral pictures from the International Affective Picture System, and the unpleasantness/pleasantness of the pictures was rated. Second, visual conditioning stimuli were presented while experimental jaw muscle pain was evoked by injection of hypertonic saline into the masseter muscle, and participants continuously rated pain intensity on an electronic visual analogue scale. The pictures induced similar changes in emotions across the 3 genotype groups, and hypertonic saline evoked moderate pain levels in all participants. However, in participants with a high expression of the serotonin transporter protein, conditioning with negative pictures increased pain intensity and positive pictures decreased pain intensity when compared with neutral pictures. In contrast, there were no significant effects of the pictures on pain perception in participants with either intermediate or low expression of the protein. These results suggest that polymorphisms in the serotonin transporter gene play an important role in emotions modulation of muscle pain.

  5. The power features of Masseter muscle activity in tension-type and migraine without aura headache during open-close clench cycles

    Directory of Open Access Journals (Sweden)

    Behrouz Alizadeh Savareh

    2017-07-01

    Full Text Available Introduction Different types of headaches and TMJ click influence the masseter muscle activity. The aim of this study was to assess the trend of energy level of the electromyography (EMG activity of the masseter muscle during open-close clench cycles in migraine without aura (MOA and tension-type headache (TTH with or without TMJ click. Methods Twenty-five women with MOA and twenty four women with TTH participated in the study. They matched with 25 healthy subjects, in terms of class of occlusion and prevalence of temporomandibular joint (TMJ with click. The EMG of both masseter muscles were recorded during open-close clench cycles at a rate of 80 cycles per minute for 15 seconds. The mouth opening was restricted to two centimeters by mandibular motion frame. Signal processing steps have been done on the EMG as: noise removing, smoothing, feature extraction, and statistical analyzing. The six statistical parameters of energy computed were mean, Variance, Skewness, Kurtosis, and first and second half energy over all signal energy. Results A three-way ANOVA indicated that during all the cycles, the mean of energy was more and there was a delay in showing the peak of energy in the masseter of the left side with clicked TMJ in MOA group compared to the two other groups, while this pattern occurred inversely in the side with no-clicked TMJ (P < 0.009. The variation of energy was significantly less in MOA group compared to the two other groups in the no-clicked TMJ (P < 0.003. However, the proportion of the first or second part of signal energy to all energy showed that TTH group had less energy in the first part and more energy in the second part in comparison to the two other groups (P < 0.05. Conclusion The study showed different changes in the energy distribution of masseter muscle activity during cycles in MOA and TTH. MOA, in contrast to TTH, had lateralization effect on EMG and interacted with TMJ click.

  6. Experimental knee pain reduces muscle strength

    DEFF Research Database (Denmark)

    Henriksen, Marius; Rosager, Sara; Aaboe, Jens

    2011-01-01

    Pain is the principal symptom in knee pathologies and reduced muscle strength is a common observation among knee patients. However, the relationship between knee joint pain and muscle strength remains to be clarified. This study aimed at investigating the changes in knee muscle strength following...... experimental knee pain in healthy volunteers, and if these changes were associated with the pain intensities. In a crossover study, 18 healthy subjects were tested on 2 different days. Using an isokinetic dynamometer, maximal muscle strength in knee extension and flexion was measured at angular velocities 0....... Knee pain reduced the muscle strength by 5 to 15% compared to the control conditions (P muscle strength was positively correlated to the pain intensity. Experimental knee pain significantly reduced knee extension...

  7. Future perspectives: pathogenesis of chronic muscle pain.

    Science.gov (United States)

    Staud, Roland

    2007-06-01

    Chronic painful muscle conditions include non-inflammatory and inflammatory illnesses. This review is focused on chronic non-inflammatory pain conditions such as myofascial pain syndrome (MPS) and fibromyalgia syndrome (FM), and will not discuss metabolic, genetic or inflammatory muscle diseases such as McArdle's disease, muscular dystrophy, polymyositis, dermatomyositis, or inclusion body myositis.

  8. Muscle strength in patients with chronic pain

    NARCIS (Netherlands)

    van Wilgen, C.P.; Akkerman, L.; Wieringa, J.; Dijkstra, P.U.

    2003-01-01

    Objective: To analyse the influence of chronic pain on muscle strength. Design: Muscle strength of patients with unilateral nonspecific chronic pain, in an upper or lower limb, were measured according to a standardized protocol using a hand-held dynamometer. Before and after muscle strength

  9. Muscle strength in patients with chronic pain

    NARCIS (Netherlands)

    van Wilgen, C.P.; Akkerman, L.; Wieringa, J.; Dijkstra, P.U.

    2003-01-01

    Objective: To analyse the influence of chronic pain on muscle strength. Design: Muscle strength of patients with unilateral nonspecific chronic pain, in an upper or lower limb, were measured according to a standardized protocol using a hand-held dynamometer. Before and after muscle strength measurem

  10. Medicines for Pain: From Osteoarthritis to Muscle Pain

    Science.gov (United States)

    Medicines for Pain: From Osteoarthritis to Muscle Pain Do you take pain medicines to treat headaches, migraines, back aches, and even joint pain? Then this ... use these types of medicine are:  People with osteoarthritis . Osteoarthritis happens when the cartilage of the joint ...

  11. Painful unilateral temporalis muscle enlargement: reactive masticatory muscle hypertrophy.

    Science.gov (United States)

    Katsetos, Christos D; Bianchi, Michael A; Jaffery, Fizza; Koutzaki, Sirma; Zarella, Mark; Slater, Robert

    2014-06-01

    An instance of isolated unilateral temporalis muscle hypertrophy (reactive masticatory muscle hypertrophy with fiber type 1 predominance) confirmed by muscle biopsy with histochemical fiber typing and image analysis in a 62 year-old man is reported. The patient presented with bruxism and a painful swelling of the temple. Absence of asymmetry or other abnormalities of the craniofacial skeleton was confirmed by magnetic resonance imaging and cephalometric analyses. The patient achieved symptomatic improvement only after undergoing botulinum toxin injections. Muscle biopsy is key in the diagnosis of reactive masticatory muscle hypertrophy and its distinction from masticatory muscle myopathy (hypertrophic branchial myopathy) and other non-reactive causes of painful asymmetric temporalis muscle enlargement.

  12. Effects of gadolinium chloride on basal flow and compression-induced rapid hyperemia in the rabbit masseter muscle.

    Science.gov (United States)

    Turturici, M; Roatta, S

    2014-06-01

    Aim of the present study is to investigate the role of mechano-sensitive channels on basal muscle blood flow and on the compression-induced rapid hyperaemia. To this aim, the mechano-sensitive channel blocker Gadolinium (Gd(3+)) is employed, which already proved to reduce the myogenic response in isolated vessels. Muscle blood flow (MaBF) was recorded from the masseteric artery in 8 urethane-anesthetized rabbits. Rapid hyperemic responses were evoked by 1-s lasting compressions of the masseter muscle (MC) delivered before and after close arterial infusion of Gd(3+) in the masseteric artery. Three infusions were performed at 1-h interval, producing estimated plasma concentration (EPC) of 0.045, 0.45 and 4.5 mM, in the masseteric artery. The amplitude of the hyperaemic response to MC, equal to 195±77% of basal flow in control condition, was reduced by 9.5±19.4% (p=0.18) and 45±28% (p<0.01) while basal MaBf increased by 10±3% (p=0.90) and by 68±30% (p<0.01) at EPC of 0.045 and 0.45 mM, respectively. At EPC of 4.5 mM a strong reduction in both MaBF (by 54±13%, p<0.01) and MC response (75±12%, p<0.01) was instead observed. These effects did not depend on time from infusion. At all doses employed Gd(3+) never affected arterial blood pressure, heart rate and contralateral MaBF. While the effects observed at the highest EPC likely result from blood vessel occlusion due to Gd(3+) precipitation, the effects observed at lower concentrations demonstrate that Gd(3+) affects musculo-vascular function by decreasing both resting vascular tone and responsiveness to mechanical stimuli. The results are compatible with a Gd(3+)-induced blockade of vascular mechano-sensitive channels.

  13. Masticatory muscle pain: Causes, consequences, and diagnosis

    NARCIS (Netherlands)

    Koutris, M.

    2013-01-01

    Masticatory muscle pain is known as myogenous temporomandibular disorder (TMD) pain. It has a prevalence of approximately 10% in the general population and affects women more than men. It is usually characterized by a dull, aching pain, which aggravates on function. The etiology of TMD pain is still

  14. [Quantitative topographic characterization of the myoelectric activity distribution of the masseter muscle: mapping of spectral EMG parameters].

    Science.gov (United States)

    Scholle, H C; Schumann, N P; Anders, C; Mey, E

    1992-09-01

    A new method for quantitative characterization of myoelectrical masseter activity distribution by mapping of spectral EMG-parameters is described. The surface electromyograms of M. masseter were monopolarly recorded (16 channels). On the basis of registered EMG intervals (512 ms) the spectral EMG power of several frequency bands was calculated (Fast Fourier Transformation). The spectral EMG parameters between the 16 electrode positions were estimated by linear interpolation (4-nearest neighbours algorithm). Afterwards the spectral EMG parameters were fitted in a grey-tone or colour scale with 10 intervals. The so obtained EMG activity maps ("EMG-Maps") permit a quantitative-topographic characterization of myoelectrical masseter activity during different functional load procedures. The frequency range which is to consider in masseter surface-EMG investigations encloses frequencies between 15 and 500 Hz. The topography of EMG activation pattern of M. masseter is only described in a comprehensive manner when the electrode array consists of 16 electrodes and more. During defined motor tasks like clenching with controlled forces the reproducibility of EMG-Maps which respect to the topography of EMG activity pattern is very high. The absolute values of spectral EMG power as well as power changes of selected band ranges during clenching correlate to the extent of chewing forces.

  15. GABAB receptors in the NTS mediate the inhibitory effect of trigeminal nociceptive inputs on parasympathetic reflex vasodilation in the rat masseter muscle.

    Science.gov (United States)

    Ishii, Hisayoshi; Izumi, Hiroshi

    2012-03-15

    The present study was designed to examine whether trigeminal nociceptive inputs are involved in the modulation of parasympathetic reflex vasodilation in the jaw muscles. This was accomplished by investigating the effects of noxious stimulation to the orofacial area with capsaicin, and by microinjecting GABA(A) and GABA(B) receptor agonists or antagonists into the nucleus of the solitary tract (NTS), on masseter hemodynamics in urethane-anesthetized rats. Electrical stimulation of the central cut end of the cervical vagus nerve (cVN) in sympathectomized animals bilaterally increased blood flow in the masseter muscle (MBF). Increases in MBF evoked by cVN stimulation were markedly reduced following injection of capsaicin into the anterior tongue in the distribution of the lingual nerve or lower lip, but not when injected into the skin of the dorsum of the foot. Intravenous administration of either phentolamine or propranolol had no effect on the inhibitory effects of capsaicin injection on the increases of MBF evoked by cVN stimulation, which were largely abolished by microinjecting the GABA(B) receptor agonist baclofen into the NTS. Microinjection of the GABA(B) receptor antagonist CGP-35348 into the NTS markedly attenuated the capsaicin-induced inhibition of MBF increase evoked by cVN stimulation, while microinjection of the GABA(A) receptor antagonist bicuculline did not. Our results indicate that trigeminal nociceptive inputs inhibit vagal-parasympathetic reflex vasodilation in the masseter muscle and suggest that the activation of GABA(B) rather than GABA(A) receptors underlies the observed inhibition in the NTS.

  16. Referred pain areas of active myofascial trigger points in head, neck, and shoulder muscles, in chronic tension type headache.

    Science.gov (United States)

    Fernández-de-Las-Peñas, César; Ge, Hong-You; Alonso-Blanco, Cristina; González-Iglesias, Javier; Arendt-Nielsen, Lars

    2010-10-01

    Our aim was to analyze the differences in the referred pain patterns and size of the areas of those myofascial trigger points (TrPs) involved in chronic tension type headache (CTTH) including a number of muscles not investigated in previous studies. Thirteen right handed women with CTTH (mean age: 38 ± 6 years) were included. TrPs were bilaterally searched in upper trapezius, sternocleidomastoid, splenius capitis, masseter, levator scapulae, superior oblique (extra-ocular), and suboccipital muscles. TrPs were considered active when both local and referred pain evoked by manual palpation reproduced total or partial pattern similar to a headache attack. The size of the referred pain area of TrPs of each muscle was calculated. The mean number of active TrPs within each CTTH patient was 7 (95% CI 6.2-8.0). A greater number (T = 2.79; p = 0.016) of active TrPs was found at the right side (4.2 ± 1.5) when compared to the left side (2.9 ± 1.0). TrPs in the suboccipital muscles were most prevalent (n = 12; 92%), followed by the superior oblique muscle (n =11/n = 9 right/left side), the upper trapezius muscle (n = 11/n = 6) and the masseter muscle (n = 9/n=7). The ANOVA showed significant differences in the size of the referred pain area between muscles (F = 4.7, p = 0.001), but not between sides (F = 1.1; p = 0.3): as determined by a Bonferroni post hoc analysis the referred pain area elicited by levator scapulae TrPs was significantly greater than the area from the sternocleidomastoid (p = 0.02), masseter (p = 0.003) and superior oblique (p = 0.001) muscles. Multiple active TrPs exist in head, neck and shoulder muscles in women with CTTH. The referred pain areas of TrPs located in neck muscles were larger than the referred pain areas of head muscles. Spatial summation of nociceptive inputs from multiple active TrPs may contribute to clinical manifestations of CTTH. Copyright © 2009 Elsevier Ltd. All rights reserved.

  17. Cysticercosis of the masseter

    Directory of Open Access Journals (Sweden)

    Prabhath Ramakrishnan

    2012-01-01

    Full Text Available Cysticercosis of the oral cavity is a very rare soft tissue lesion and very few cases have been reported worldwide. Here we report a case of a cysticercous cellulosae within the masseter muscle which was diagnosed with the help of high resolution ultrasonography (USG and ultrasound guided fine needle aspiration cytology (FNAC and managed conservatively using oral antiparasitic medication. Cysticercosis is not commonly considered in the diagnosis of swellings of the head and neck and this is the reason why they are of utmost interest to the practitioner and have to be studied.

  18. Management of trismus by masseter myotomy

    Directory of Open Access Journals (Sweden)

    Sonal Bhavesh Shah

    2014-01-01

    Full Text Available Mild trismus after parotid gland surgery may be related to inflammation and fibrosis of the masseter muscle. We present a case of long standing trismus due to masseter muscle spasm caused by a recurrent pleomorphic adenoma. As the patient did not agree for removal of the pleomaorphic adenoma, owing to the risk of injuring the facial nerve, a masseter myotomy with inter-positioning of temporalis fascia was planned for symptomatic relief. Mouth opening showed significant improvement even 1 year post-operatively.

  19. Evidence that the contraction-induced rapid hyperemia in rabbit masseter muscle is based on a mechanosensitive mechanism, not shared by cutaneous vascular beds.

    Science.gov (United States)

    Turturici, Marco; Mohammed, Mazher; Roatta, Silvestro

    2012-08-15

    Several mechanisms have been hypothesized to contribute to the rapid hyperemia at the onset of exercise. The aim of the present study was to investigate the role played by the mechanosensitivity of the vascular network. In 12 anesthetized rabbits blood flow was recorded from the exclusively muscular masseteric artery in response to brief spontaneous contractions (BSC) of the masseter muscle, artery occlusion (AO), muscle compression (MC), and muscle stretch (MS). Activation of masseter muscle was monitored by electromyography (EMG). Responses to AO were also recorded from the mostly cutaneous facial and the central ear arteries. Five animals were also tested in the awake condition. The hyperemic response to BSC (peak amplitude of 394 ± 82%; time to peak of 1.8 ± 0.8 s) developed with a latency of 300-400 ms from the beginning of the EMG burst and 200-300 ms from the contraction-induced transient flow reduction. This response was neither different from the response to AO (peak amplitude = 426 ± 158%), MC, and MS (P = 0.23), nor from the BSC response in the awake condition. Compared with the masseteric artery, the response to AO was markedly smaller both in the facial (83 ± 18%,) and in the central ear artery (68 ± 20%) (P < 0.01). In conclusion, the rapid contraction-induced hyperemia can be replicated by a variety of stimuli affecting transmural pressure in muscle blood vessels and is thus compatible with the Bayliss effect. This prominent mechanosensitivity appears to be a characteristic of muscle and not cutaneous vascular beds.

  20. Effect of muscle relaxants on experimental jaw-muscle pain and jaw-stretch reflexes: a double-blind and placebo-controlled trial.

    Science.gov (United States)

    Svensson, Peter; Wang, Kelun; Arendt-Nielsen, Lars

    2003-01-01

    A randomised, double-blind, placebo-controlled three-way cross-over study was performed to investigate the effect of two muscle relaxants (tolperisone hydrochloride and pridinol mesilate) on experimental jaw-muscle pain and jaw-stretch reflexes. Fifteen healthy men participated in three randomised sessions separated by at least 1 week. In each session 300 mg tolperisone, 8 mg pridinol mesilate or placebo was administered orally as a single dose. One hour after drug administration 0.3 ml hypertonic saline (5.8%) was injected into the right masseter to produce muscle pain. Subjects continuously rated their perceived pain intensity on an electronic 10-cm visual analogue scale (VAS). The pressure pain threshold (PPT) was measured and short-latency reflex responses were evoked in the pre-contracted (15% maximal voluntary contraction) masseter and temporalis muscles by a standardised stretch device (1 mm displacement, 10 ms ramp time) before (baseline), 1 h after medication (post-drug), during ongoing experimental muscle pain (pain-post-drug), and 15 min after pain had vanished (post-pain). Analysis of variance demonstrated significantly lower VAS peak pain scores (5.9 +/- 0.4 cm) after administration of tolperisone hydrochloride compared with pridinol mesilate (6.8 +/- 0.4 cm) and placebo (6.6 +/- 0.4 cm) (P=0.020). Administration of pridinol mesilate was associated with a significant decrease in PPTs compared with tolperisone hydrochloride and placebo (P=0.002) after medication, but not after experimental jaw-muscle pain. The normalised peak-to-peak amplitude of the stretch reflexes were not significantly influenced by the test medication (P=0.762), but were in all sessions significantly facilitated during ongoing experimental jaw-muscle pain (P=0.034). In conclusion, tolperisone hydrochloride provides a small, albeit significant reduction in the perceived intensity of experimental jaw-muscle pain whereas the present dose had no effect on the short-latency jaw

  1. Bilateral experimental neck pain reorganize axioscapular muscle coordination and pain sensitivity

    DEFF Research Database (Denmark)

    Christensen, Steffan Wittrup; Hirata, Rogerio Pessoto; Graven-Nielsen, Thomas

    2017-01-01

    BACKGROUND: Neck pain is a large clinical problem where reorganized trunk and axioscapular muscle activities have been hypothesised contributing to pain persistence and pain hypersensitivity. This study investigated the effects of bilateral experimental neck pain on trunk and axioscapular muscle ...

  2. The influence of experimentally induced pain on shoulder muscle activity

    DEFF Research Database (Denmark)

    Diederichsen, L.P.; Winther, A.; Dyhre-Poulsen, P.

    2009-01-01

    muscles. EMG was recorded before pain, during pain and after pain had subsided and pain intensity was continuously scored on a visual analog scale (VAS). During abduction, experimentally induced pain in the supraspinatus muscle caused a significant decrease in activity of the anterior deltoid, upper...... in a way that protects the painful structure. Further, the changes in muscle activity following subacromial pain induction tend to expand the subacromial space and thereby decrease the load on the painful structures Udgivelsesdato: 2009/4...

  3. Assessment of pain sensitivity in patients with deep bite and sex- and age-matched controls

    DEFF Research Database (Denmark)

    Sonnesen, Ane Liselotte; Svensson, Peter

    2011-01-01

    AIMS: To compare pain sensitivity between deep bite patients and a sex- and age-matched control group with normal occlusion. METHODS: Pain sensitivity was assessed by injections of the excitatory amino acid glutamate into the masseter and brachioradialis muscles. Intensity of glutamate-evoked pain...... was scored by the subjects ( n = 60) on a 0 to 10 cm visual analog scale. Subjects drew the perceived pain area on a face and arm chart and described the quality of pain on the McGill Pain Questionnaire. Thresholds for cold detection, cold pain, cold tolerance, warmth detection, heat pain, and heat tolerance...... were assessed on the masseter and brachioradialis muscles. Pressure pain threshold and pain tolerance threshold were determined on the temporomandibular joint, masseter, anterior temporalis, and brachioradialis muscles. The differences between groups, age, and gender were tested by two-way ANOVA...

  4. Correlation between the clinical phonoaudiological assessment and electromyographic activity of the masseter muscle Correlação entre a avaliação clínico-fonoaudiológica e a eletromiográfica do músculo masseter

    Directory of Open Access Journals (Sweden)

    Daiana Cristina Biasotto

    2005-12-01

    Full Text Available OBJECTIVE: The objective of this paper was to evaluate the specificity of masseter muscle palpation when compared to its electromyographic activity. MATERIALS AND METHODS: Twenty-one young female adults, aged between 17 and 25, participated in this research. The speech therapy evaluation data were obtained by two speech therapists through masseter muscle palpation during isometric contraction, and the electromyographic exam was achieved by using bipolar superficial electrodes, positioned on the masseter muscle. The volunteers were instructed to chew the Parafilm M® material bilaterally and simultaneously. The capture of the electromiographic signals occurred during masseter muscle isometric contractions. The electrical activity study of the masticatory muscle was analyzed through the Root Mean Square value during its isotonic contraction. STATISTICAL ANALYSIS: All data were then submitted to Kappa statistical analysis. RESULTS: The results of this study have shown a low correlation between palpation and electromyography (25%, as well as between evaluators (40%. CONCLUSION: According to the findings of the present study, it could be observed that the correlation between masseter muscle palpation and its electromyographic activity was very low, which allows to conclude that muscular palpation cannot effectively replace the eletromyographical exam, but complement it instead.OBJETIVO: Este trabalho teve como objetivo avaliar a correlação entre os resultados obtidos na palpação e os dados obtidos no exame eletromiográfico do músculo masseter. MATERIAL E MÉTODO: Participaram deste estudo 21 adultos jovens do sexo feminino, idades entre 17-25 anos. Os dados da avaliação fonoaudiológica foram obtidos por meio da palpação do músculo masseter durante a contração isométrica por dois fonoaudiólogos e os dados eletromiográficos foram captados com a utilização de eletrodos de superfície bipolares posicionados no músculo masseter durante

  5. Painful Unilateral Temporalis Muscle Enlargement: Reactive Masticatory Muscle Hypertrophy

    OpenAIRE

    Katsetos, Christos D.; Bianchi, Michael A.; Jaffery, Fizza; Koutzaki, Sirma; Zarella, Mark; Slater, Robert

    2013-01-01

    An instance of isolated unilateral temporalis muscle hypertrophy (reactive masticatory muscle hypertrophy with fiber type 1 predominance) confirmed by muscle biopsy with histochemical fiber typing and image analysis in a 62 year-old man is reported. The patient presented with bruxism and a painful swelling of the temple. Absence of asymmetry or other abnormalities of the craniofacial skeleton was confirmed by magnetic resonance imaging and cephalometric analyses. The patient achieved symptoma...

  6. A intervenção fonoaudiológica no pós-operatório da hipertrofia benigna do músculo masseter The miofunctional oral intervention in the surgery treatment for the masseter muscle hipertrophy

    OpenAIRE

    Laura Davison Mangilli; Christiane Siman Rodrigues; Alcione Ramos Campiotto

    2006-01-01

    OBJETIVO: descrever a abordagem fonoaudiológica no pós-operatório de pacientes que realizaram correção cirúrgica da hipertrofia do músculo masseter. METODOLOGIA: foram coletados dados referentes à avaliação e ao tratamento fonoaudiológico de 4 prontuários de sujeitos de ambos os gêneros, com faixa etária entre 16 e 24 anos, com hipertrofia benigna do músculo masseter, tratados cirurgicamente. RESULTADOS: as principais queixas pós-cirúrgicas estiveram relacionadas à limitação da abertura da bo...

  7. The influence of experimentally induced pain on shoulder muscle activity

    DEFF Research Database (Denmark)

    Diederichsen, Louise Pyndt; Winther, Annika; Dyhre-Poulsen, Poul

    2009-01-01

    . EMG was recorded before pain, during pain and after pain had subsided and pain intensity was continuously scored on a visual analog scale (VAS). During abduction, experimentally induced pain in the supraspinatus muscle caused a significant decrease in activity of the anterior deltoid, upper trapezius...... the painful structure. Further, the changes in muscle activity following subacromial pain induction tend to expand the subacromial space and thereby decrease the load on the painful structures....

  8. Involvement of trigeminal transition zone and laminated subnucleus caudalis in masseter muscle hypersensitivity associated with tooth inflammation.

    Directory of Open Access Journals (Sweden)

    Kohei Shimizu

    Full Text Available A rat model of pulpitis/periapical periodontitis was used to study mechanisms underlying extraterritorial enhancement of masseter response associated with tooth inflammation. Periapical bone loss gradually increased and peaked at 6 weeks after complete Freund's adjuvant (CFA application to the upper molar tooth pulp (M1. On day 3, the number of Fos-immunoreactive (IR cells was significantly larger in M1 CFA rats compared with M1 vehicle (veh rats in the trigeminal subnucleus interpolaris/caudalis transition zone (Vi/Vc. The number of Fos-IR cells was significantly larger in M1 CFA and masseter (Mass capsaicin applied (M1 CFA/Mass cap rats compared with M1 veh/Mass veh rats in the contralateral Vc and Vi/Vc. The number of phosphorylated extracellular signal-regulated kinase (pERK-IR cells was significantly larger in M1 CFA/Mass cap and M1 veh/Mass cap rats compared to Mass-vehicle applied rats with M1 vehicle or CFA in the Vi/Vc. Pulpal CFA application caused significant increase in the number of Fos-IR cells in the Vi/Vc but not Vc on week 6. The number of pERK-IR cells was significantly lager in the rats with capsaicin application to the Mass compared to Mass-vehicle treated rats after pulpal CFA- or vehicle-application. However, capsaicin application to the Mass did not further affect the number of Fos-IR cells in the Vi/Vc in pulpal CFA-applied rats. The digastric electromyographic (d-EMG activity after Mass-capsaicin application was significantly increased on day 3 and lasted longer at 6 weeks after pulpal CFA application, and these increase and duration were significantly attenuated by i.t. PD98059, a MEK1 inhibitor. These findings suggest that Vi/Vc and Vc neuronal excitation is involved in the facilitation of extraterritorial hyperalgesia for Mass primed with periapical periodontitis or acute pulpal-inflammation. Furthermore, phosphorylation of ERK in the Vi/Vc and Vc play pivotal roles in masseter hyperalgesia after pulpitis or

  9. The relationship between masseter force and masseter electromyogram during mastication in the monkey Macaca fascicularis.

    Science.gov (United States)

    Hylander, W L; Johnson, K R

    1989-01-01

    In five adult monkeys, electromyograms (EMGs) were recorded from bipolar surface electrodes positioned over the superficial masseter and from bipolar fine-wire electrodes within both the superficial and deep masseter. Relative masseter force was estimated by measuring surface bone strain from the lateral aspect of the zygomatic arch using rosette strain gauges. Multiple step-wise regression procedures demonstrated that peak values of the averaged masseter EMG could often explain a considerable amount of the variation of peak relative masseter force during mastication, i.e. r2 values ranged from 0.23 to 0.96 for the various single-electrode models and R2 values ranged from 0.78 to 0.96 for the various multiple-electrode models. The r2 values for relative masseter force and EMG data from the surface electrodes ranged from 0.69 to 0.96, and, on average, EMG data from surface electrodes provided somewhat more information about overall relative muscle force than data from fine-wire electrodes. The R2 values for a two-electrode model, consisting of data from surface electrodes over the superficial masseter and fine-wire electrodes in the posterior portion of the deep masseter, ranged from 0.78 to 0.95. The latency between the averaged surface EMG and relative muscle force was determined and the data indicated that the surface EMG usually preceded muscle force. This latency tended to decrease gradually throughout the entire power stroke of mastication. At peak values, the surface EMG preceded muscle force by about 22 ms. Towards the end of the power stroke, i.e. the 25% of peak values during unloading, muscle force may actually precede the average EMG.

  10. Development of a behavioral assessment of craniofacial muscle pain in lightly anesthetized rats.

    Science.gov (United States)

    Ro, Jin Y; Capra, Norman; Masri, Radi

    2003-07-01

    In this study, a new behavioral assessment of craniofacial muscle pain in the lightly anesthetized rat is described. Intramuscular injections with algesic agents in lightly anesthetized rats evoked a characteristic ipsilateral hindpaw shaking behavior for several minutes similar to previously described orofacial pain-induced grooming behavior in awake rats (Neurosci Lett 103 (1989) 349, Pain 62 (1995) 295). Eighty-two male Sprague-Dawley rats were used in a series of experiments to study whether this behavior could serve as a valid measure of craniofacial muscle pain. First, we demonstrated that different algesic chemicals, mustard oil (20%), formalin (3%) or hypertonic saline (5%) injected in the mid-region of the masseter muscle effectively elicited the hindpaw shaking behavior. The behavior was only minimally evoked with vehicle injection. Repeated administrations of hypertonic saline, a short duration non-sensitizing algogen, demonstrated reproducibility of the assay. Second, we showed that the peak and overall magnitude of the shaking behavior evoked by injections with different concentrations of mustard oil (1 and 5%) changed in a concentration dependent manner. Finally, we showed that systemic administration of morphine sulfate (3 and 0.3 mg/kg, i.p.) dose dependently attenuated mustard oil induced hindpaw-shaking behavior. Lidocaine injected locally 5 min prior to mustard oil injection also significantly decreased the hindpaw shaking behavior. Based on these results we concluded that ipsilateral hindpaw shaking in lightly anesthetized rats is a stereotypical behavior evoked by noxious muscle stimulation and can be used as a reliable behavioral measure to assess craniofacial muscle pain.

  11. Assessment of prevalence study of 40 variables related to painful dysfunction syndrome of masticatory muscles in patients referred to faculty of dentistry in Mashhad, Northeast of Iran

    Directory of Open Access Journals (Sweden)

    Hamed Mortazavi

    2010-06-01

    Full Text Available Introduction: Painful dysfunction syndrome of masticatory muscles is one of the most important causes of pain in orofacial region. Therefore, the aim of this study was to evaluate the prevalency of 40 variables related to this disorder. Materials and Methods: A total 39 patients (32 females, 7 males with painful dysfunction syndrome of masticatory muscles were studied. Patients were evaluated for prevalence of age, sex, job, marriage status, masticatory muscles tenderness, maximum mouth opening, deviation, deflection, temporomandibular joint involvement, habits, parafunctions, mall occlusions, neck pain, headache, ear pain and previous history of jaw involvement. Results:  Mean age of patients was 35±13.32 years old and most common range of age was  20-40, 51% were house wife and 74.4% were married. Other variables included: Clicking (74.4%, temporomandibular joint pain (54%, headache (46.2%, ear pain (41%, neck pain (35.9%, limitation of maximum opening (71.8%, class I mall occlusion (74.4%, cross bite and deep bite (25.6%, deviation (7.7%, deflection (41%, bruxism (56.4%, clenching (64.1% Masseter and external petrygoid (85% muscles of masticatoty muscles had higher involvement. Conclusion: Because of painful dysfunction syndrome of masticatory muscles has variable signs and symptoms, diagnosis and treatment planning may be very difficult, Therefore having more information about this disorder can help physicians to make best decisions.

  12. Myosin proteins identified from masseter muscle using quantitative reverse transcriptase-polymerase chain reaction--a pilot study of the relevance to orthodontics.

    Science.gov (United States)

    Suchak, Archna; Hunt, Nigel P; Shah, Rishma; Sinanan, Andrea C M; Lloyd, Tim; Lewis, Mark P

    2009-04-01

    There is a clearly established relationship between masticatory muscle structure and facial form. Human studies in this area, however, have been limited, especially in consideration of the myosin heavy chain (MyHC) family of contractile proteins. The aim of this pilot study was to assess if differences were detectable between genotype with respect to MyHC isoforms and the vertical facial phenotype in a sample of nine Caucasian female patients, age range 18-49 years, using a novel rapid technique. Masseter muscle biopsies were taken from patients with a range of vertical facial form. The levels of expression of the MyHC isoform genes MYH 1, 2, 3, 6, 7, and 8 were compared with the expression in a female calibrator patient aged 23 years with normal vertical facial form, using quantitative reverse transcriptase-polymerase chain reaction (RT-PCR) analysis. Statistical analysis was undertaken using Pearson correlation coefficient. The results showed that there were distinct differences in gene expression between patients with a wide range of variation although changes in MYH1 were consistent with one cephalometric variable, the maxillo-mandibular angle. The full procedure, from start to finish, can be completed within half a day. Rapid genotyping of patients in this way could reveal important information of relevance to treatment. This technology has potential as a diagnostic and prognostic aid when considering correction of certain malocclusions.

  13. Muscle pain: animal and human experimental and clinical studies.

    Science.gov (United States)

    Marchettini, P

    1993-10-01

    The search for the identification of the sensory apparatus encoding muscle pain sensation in humans is recounted. Basic neurophysiologic animal studies, leading to a description of slowly conducting afferent from muscle and definition of high threshold polymodal muscle nociceptors, and pioneer psychophysic human studies together with recent microneurographic experiments in humans are described. The phenomena of muscle pain broad localization and distant referral are discussed, and clinical implications are extrapolated to interpret muscle pain as a localizing sign of mononeuropathy or radiculopathy. The identification of human muscle nociceptors has defined the scientific standard to test emerging clinical descriptions having muscle pain as a symptom.

  14. Dietary glutamate will not affect pain in fibromyalgia

    NARCIS (Netherlands)

    Geenen, R.; Janssens, E.L.; Jacobs, J.W.G.; Staveren, van W.A.

    2004-01-01

    Injection of glutamate into the masseter muscle has been suggested-to evoke an increase in intensity of and sensitivity to pain. A case study showed that a diet low in monosodium glutamate (MSG) might accomplish pain relief in fibromyalgia (FM). To clarify the possible pain-modulating effect of diet

  15. Referred pain from myofascial trigger points in head and neck-shoulder muscles reproduces head pain features in children with chronic tension type headache.

    Science.gov (United States)

    Fernández-de-las-Peñas, César; Fernández-Mayoralas, Daniel M; Ortega-Santiago, Ricardo; Ambite-Quesada, Silvia; Palacios-Ceña, Domingo; Pareja, Juan A

    2011-02-01

    Our aim was to describe the referred pain pattern and areas from trigger points (TrPs) in head, neck, and shoulder muscles in children with chronic tension type headache (CTTH). Fifty children (14 boys, 36 girls, mean age: 8 ± 2) with CTTH and 50 age- and sex- matched children participated. Bilateral temporalis, masseter, superior oblique, upper trapezius, sternocleidomastoid, suboccipital, and levator scapula muscles were examined for TrPs by an assessor blinded to the children's condition. TrPs were identified with palpation and considered active when local and referred pains reproduce headache pain attacks. The referred pain areas were drawn on anatomical maps, digitalized, and also measured. The total number of TrPs was significantly greater in children with CTTH as compared to healthy children (P < 0.001). Active TrPs were only present in children with CTTH (P < 0.001). Within children with CTTH, a significant positive association between the number of active TrPs and headache duration (r (s) = 0.315; P = 0.026) was observed: the greater the number of active TrPs, the longer the duration of headache attack. Significant differences in referred pain areas between groups (P < 0.001) and muscles (P < 0.001) were found: the referred pain areas were larger in CTTH children (P < 0.001), and the referred pain area elicited by suboccipital TrPs was larger than the referred pain from the remaining TrPs (P < 0.001). Significant positive correlations between some headache clinical parameters and the size of the referred pain area were found. Our results showed that the local and referred pains elicited from active TrPs in head, neck and shoulder shared similar pain pattern as spontaneous CTTH in children, supporting a relevant role of active TrPs in CTTH in children.

  16. Management of Unilateral Masseter Hypertrophy and Hypertrophic Scar—A Case Report

    Directory of Open Access Journals (Sweden)

    Naresh Shetty

    2012-01-01

    Full Text Available Masseter muscle hypertrophy is a rare condition of idiopathic cause. It clinically presents as an enlargement of one or both masseter muscles. Most patients complain of facial asymmetry; however, symptoms such as trismus, protrusion, and bruxism may also occur. Several treatment options reported for masseter hypertrophy are present, which range from simple pharmacotherapy to more invasive surgical reduction. Keloid scar with unilateral masseter hypertrophy is a rarely seen in clinical practice. This paper reports a case of unilateral masseter hypertrophy with keloid scar in the angle of the mandible for which surgical treatment was rendered to the patient by using a single approach.

  17. Referred pain from myofascial trigger points in head, neck, shoulder, and arm muscles reproduces pain symptoms in blue-collar (manual) and white-collar (office) workers.

    Science.gov (United States)

    Fernández-de-las-Peñas, César; Gröbli, Christian; Ortega-Santiago, Ricardo; Fischer, Christine Stebler; Boesch, Daniel; Froidevaux, Philippe; Stocker, Lilian; Weissmann, Richard; González-Iglesias, Javier

    2012-07-01

    To describe the prevalence and referred pain area of trigger points (TrPs) in blue-collar (manual) and white-collar (office) workers, and to analyze if the referred pain pattern elicited from TrPs completely reproduces the overall spontaneous pain pattern. Sixteen (62% women) blue-collar and 19 (75% women) white-collar workers were included in this study. TrPs in the temporalis, masseter, upper trapezius, sternocleidomastoid, splenius capitis, oblique capitis inferior, levator scapulae, scalene, pectoralis major, deltoid, infraspinatus, extensor carpi radialis brevis and longus, extensor digitorum communis, and supinator muscles were examined bilaterally (hyper-sensible tender spot within a palpable taut band, local twitch response with snapping palpation, and elicited referred pain pattern with palpation) by experienced assessors blinded to the participants' condition. TrPs were considered active when the local and referred pain reproduced any symptom and the patient recognized the pain as familiar. The referred pain areas were drawn on anatomic maps, digitized, and measured. Blue-collar workers had a mean of 6 (SD: 3) active and 10 (SD: 5) latent TrPs, whereas white-collar workers had a mean of 6 (SD: 4) active and 11 (SD: 6) latent TrPs (P>0.548). No significant differences in the distribution of active and latent TrPs in the analyzed muscles between groups were found. Active TrPs in the upper trapezius, infraspinatus, levator scapulae, and extensor carpi radialis brevis muscles were the most prevalent in both groups. Significant differences in referred pain areas between muscles (Pmuscles showed the largest referred pain areas (Pmuscles showed the smallest (Pmuscle TrPs in blue-collar and white-collar workers.

  18. Avaliação eletromiográfica do músculo masseter em pessoas com paralisia facial periférica de longa duração Masseter muscle electromyographic assessment in subject with long lasting facial palsy

    Directory of Open Access Journals (Sweden)

    Adriana Rahal

    2007-06-01

    Full Text Available OBJETIVO: verificar a atividade elétrica do músculo masseter em pessoas com paralisia facial periférica de longa duração. MÉTODOS: participaram deste estudo seis sujeitos de ambos os sexos, com paralisia facial há pelo menos doze meses, sem queixas mastigatórias e sem disfunção temporomandibular e com pelo menos seis dentes em cada hemiarcada. Todos preencheram um questionário de anamnese e em seguida foram submetidos à eletromiografia de superfície dos masseteres de ambos os lados. As provas eletromiográficas foram: posição habitual com lábios fechados, apertamento dentário, mastigação habitual e unilateral à direita e à esquerda com uva passa. RESULTADOS: em todas as provas eletromiográficas não foram observadas diferenças significantes (p=0,05 entre os lados com e sem paralisia facial. CONCLUSÃO: observou-se com o presente estudo que a força do músculo masseter não sofre influência da paralisia facial de longa duração.PURPOSE: to check the masseter electrical activity in long lasting facial paralysis patients. METHODS: six subjects, with facial paralysis for over a period of twelve months, males and females, took part in this study. Patients should not show any masticatory complaints or have any diagnoses of temporo-mandibular joint dysfunction, having at least six teeth in each half dental ridge. All subjects filled out a questionnaire regarding oral habits and were assessed by surface electromyography of the masseter muscle of both sides. Electromyographic records were taken with lips closed at rest, teeth tightness, besides usual mastication, and unilateral mastication on both sides with raisins. RESULTS: in all electromyographic tests there were no statistically significant differences (p=0.05 between both sides, with and without facial paralysis. CONCLUSION: it was observed that the strength of the masseter muscle is not under the influence of long lasting facial paralysis.

  19. The influence of experimentally induced pain on shoulder muscle activity.

    Science.gov (United States)

    Diederichsen, Louise Pyndt; Winther, Annika; Dyhre-Poulsen, Poul; Krogsgaard, Michael R; Nørregaard, Jesper

    2009-04-01

    Muscle function is altered in painful shoulder conditions. However, the influence of shoulder pain on muscle coordination of the shoulder has not been fully clarified. The aim of the present study was to examine the effect of experimentally induced shoulder pain on shoulder muscle function. Eleven healthy men (range 22-27 years), with no history of shoulder or cervical problems, were included in the study. Pain was induced by 5% hypertonic saline injections into the supraspinatus muscle or subacromially. Seated in a shoulder machine, subjects performed standardized concentric abduction (0 degrees -105 degrees) at a speed of approximately 120 degrees/s, controlled by a metronome. During abduction, electromyographic (EMG) activity was recorded by intramuscular wire electrodes inserted in two deeply located shoulder muscles and by surface-electrodes over six superficially located shoulder muscles. EMG was recorded before pain, during pain and after pain had subsided and pain intensity was continuously scored on a visual analog scale (VAS). During abduction, experimentally induced pain in the supraspinatus muscle caused a significant decrease in activity of the anterior deltoid, upper trapezius and the infraspinatus and an increase in activity of lower trapezius and latissimus dorsi muscles. Following subacromial injection a significantly increased muscle activity was seen in the lower trapezius, the serratus anterior and the latissimus dorsi muscles. In conclusion, this study shows that acute pain both subacromially and in the supraspinatus muscle modulates coordination of the shoulder muscles during voluntary movements. During painful conditions, an increased activity was detected in the antagonist (latissimus), which support the idea that localized pain affects muscle activation in a way that protects the painful structure. Further, the changes in muscle activity following subacromial pain induction tend to expand the subacromial space and thereby decrease the load

  20. The effect of nonfunctional tooth contact on sensory and pain perception in patients with myofascial pain of the jaw muscles.

    Science.gov (United States)

    Okayasu, Ichiro; Oi, Kumiko; De Laat, Antoon

    2012-04-01

    The aim of this study was to examine the effect of nonfunctional tooth contact on sensory threshold (tactile detection threshold: TDT) and pain thresholds (filament-prick pain detection threshold: FPT; pressure pain threshold: PPT) in the orofacial region of patients with myofascial pain of the jaw muscles. The study was performed on 36 subjects: 20 normal subjects and 16 patients. Using a stair-case method, TDT and FPT were measured by Semmes-Weinstein monofilaments, on the cheek skin (CS) overlying the masseter muscles (MM) and on the skin overlying the palm side of the thenar skin (TS). PPT was measured at the central part of the MM using a pressure algometer. Each parameter was measured before and after keeping light tooth contact for 5 min (session 1) and keeping the jaw relaxed for 5 min (session 2) as a control. There were significant effects of experimental condition (before-after 5 min) on the TDT and FPT at several sites: after 5 min, TDT was higher in all measurement sites except the left CS of the patients in session 2. As for the FPT, the reactions between CS and TS were quite opposite in both sessions: after 5 min, the FPT at the CS decreased and/or remained, but the FPT at the TS increased and/or remained. Significant session effects (session 1-session 2) were only found on the FPT at the CS in patients. Sensitivity to FPT was more susceptible to tooth contact condition, especially in the patients. Copyright © 2011 Japan Prosthodontic Society. Published by Elsevier Ltd. All rights reserved.

  1. Craniofacial muscle pain: review of mechanisms and clinical manifestations.

    Science.gov (United States)

    Svensson, P; Graven-Nielsen, T

    2001-01-01

    Epidemiologic surveys of temporomandibular disorders (TMD) have demonstrated that a considerable proportion of the population--up to 5% or 6%--will experience persistent pain severe enough to seek treatment. Unfortunately, the current diagnostic classification of craniofacial muscle pain is based on descriptions of signs and symptoms rather than on knowledge of pain mechanisms. Furthermore, the pathophysiology and etiology of craniofacial muscle pain are not known in sufficient detail to allow causal treatment. Many hypotheses have been proposed to explain cause-effect relationships; however, it is still uncertain what may be the cause of muscle pain and what is the effect of muscle pain. This article reviews the literature in which craniofacial muscle pain has been induced by experimental techniques in animals and human volunteers and in which the effects on somatosensory and motor function have been assessed under standardized conditions. This information is compared to the clinical correlates, which can be derived from the numerous cross-sectional studies in patients with craniofacial muscle pain. The experimental literature clearly indicates that muscle pain has significant effects on both somatosensory and craniofacial motor function. Typical somatosensory manifestations of experimental muscle pain are referred pain and increased sensitivity of homotopic areas. The craniofacial motor function is inhibited mainly during experimental muscle pain, but phase-dependent excitation is also found during mastication to reduce the amplitude and velocity of jaw movements. The underlying neurobiologic mechanisms probably involve varying combinations of sensitization of peripheral afferents, hyperexcitability of central neurons, and imbalance in descending pain modulatory systems. Reflex circuits in the brain stem seem important for the adjustment of sensorimotor function in the presence of craniofacial pain. Changes in somatosensory and motor function may therefore be

  2. Muscle strength, pain and disability in patients with osteoarthritis.

    NARCIS (Netherlands)

    Steultjens, M.P.M.; Dekker, J.; Baar, M.E. van; Oostendorp, R.A.B.; Bijlsma, J.W.J.

    2001-01-01

    Objective: Reduced muscle strength is regarded as a risk factor for pain and disability in osteoarthritis (OA). Currently, various indices for muscle strength are used when assessing determinants of pain and disability. The goal of the present study was to evaluate these indices of muscle strength.

  3. Muscle strength, pain and disability in patients with osteoarthritis.

    NARCIS (Netherlands)

    Steultjens, M.P.M.; Dekker, J.; Baar, M.E. van; Oostendorp, R.A.B.; Bijlsma, J.W.J.

    2001-01-01

    Objective: Reduced muscle strength is regarded as a risk factor for pain and disability in osteoarthritis (OA). Currently, various indices for muscle strength are used when assessing determinants of pain and disability. The goal of the present study was to evaluate these indices of muscle strength.

  4. Frequency of daytime tooth clenching episodes in individuals affected by masticatory muscle pain and pain-free controls during standardized ability tasks.

    Science.gov (United States)

    Cioffi, Iacopo; Landino, Donatella; Donnarumma, Valeria; Castroflorio, Tommaso; Lobbezoo, Frank; Michelotti, Ambrosina

    2017-05-01

    Tooth clenching has been suggested to be related to temporomandibular pain. However, the electromyographic characteristics of daytime clenching episodes have been minimally investigated. This study aimed to analyze the frequency, amplitude, and duration of daytime clenching episodes in patients with masticatory muscle pain and pain-free individuals. Fifteen women with masticatory muscles myalgia (MP group, mean ± SD age = 26.4 ± 7.6 years) matched for age to 18 pain-free women (CTR group, mean ± SD age = 25.3 ± 2.8 years) were submitted to three different ability tasks (filling out questionnaires for 40 min, reading for 20 min, and playing a videogame for 20 min). The electromyographic activity periods (AP) of the right masseter greater than 10 % (AP10), 20 % (AP20), and 30 % (AP30) of the maximum voluntary contraction were analyzed. The mean frequencies of AP10, AP20, and AP30 were greater in MP than in CTR individuals (all p pain have an increased frequency of both high and low-intense daytime clenching episodes. The type of ability task affects the frequency and the duration of clenching episodes only in pain-free individuals. Clinicians should recognize that the frequency and intensity of daytime clenching are noticeably increased in individuals with masticatory muscle pain in order to better tailor treatment.

  5. Downregulation of selective microRNAs in trigeminal ganglion neurons following inflammatory muscle pain

    Directory of Open Access Journals (Sweden)

    Wei Dong

    2007-06-01

    Full Text Available Abstract Active regulation of gene expression in the nervous system plays an important role in the development and/or maintenance of inflammatory pain. MicroRNA (miRNA negatively regulates gene expression via posttranscriptional or transcriptional inhibition of specific genes. To explore the possible involvement of miRNA in gene regulation during inflammatory pain, we injected complete Freund's adjuvant (CFA unilaterally into the rat masseter muscle and quantified changes in neuron-specific mature miRNAs in the trigeminal ganglion (TG. Real-time reverse-transcription polymerase chain reaction revealed significant, but differential, downregulation of mature miR-10a, -29a, -98, -99a, -124a, -134, and -183 in the ipsilateral mandibular division (V3 of the TG within 4 hr after CFA. In contrast, levels of tested miRNAs did not change significantly in the contralateral V3 or the ipsilateral ophthalmic and maxillary divisions of the TG from inflamed rats, nor in the ipsilateral V3 of saline-injected animals. The downregulated miRNAs recovered differentially to a level equal to or higher than that in naive animals. Full recovery time varied with miRNA species but was at least 4 days. Expression and downregulation of some miRNAs were further confirmed by in situ hybridization of TG neurons that innervate the inflamed muscle. Although neurons of all sizes expressed these miRNAs, their signals varied between neurons. Our results indicate that miRNA species specific to neurons are quickly regulated following inflammatory muscle pain.

  6. Identification of the occurrence and pattern of masseter muscle activities during sleep using EMG and accelerometer systems

    Directory of Open Access Journals (Sweden)

    Sato Sadao

    2009-02-01

    Full Text Available Abstract Background Sleep bruxism has been described as a combination of different orofacial motor activities that include grinding, clenching and tapping, although accurate distribution of the activities still remains to be clarified. Methods We developed a new system for analyzing sleep bruxism to examine the muscle activities and mandibular movement patterns during sleep bruxism. The system consisted of a 2-axis accelerometer, electroencephalography and electromyography. Nineteen healthy volunteers were recruited and screened to evaluate sleep bruxism in the sleep laboratory. Results The new system could easily distinguish the different patterns of bruxism movement of the mandible and the body movement. Results showed that grinding (59.5% was most common, followed by clenching (35.6% based on relative activity to maximum voluntary contraction (%MVC, whereas tapping was only (4.9%. Conclusion It was concluded that the tapping, clenching, and grinding movement of the mandible could be effectively differentiated by the new system and sleep bruxism was predominantly perceived as clenching and grinding, which varied between individuals.

  7. Muscle function and origin of pain in fibromyalgia

    DEFF Research Database (Denmark)

    Bennett, R M; Jacobsen, Søren

    1994-01-01

    It may be concluded that both peripheral and central mechanisms may operate in the pathophysiology of both impaired muscle function and pain in FM. These mechanisms may in part be attributable to physical deconditioning and disuse of muscle secondary to the characteristic pain and fatigue so ofte...

  8. Craniofacial pain and jaw-muscle activity during sleep.

    Science.gov (United States)

    Yachida, W; Castrillon, E E; Baad-Hansen, L; Jensen, R; Arima, T; Tomonaga, A; Ohata, N; Svensson, P

    2012-06-01

    This study compared the jaw-muscle electromyographic (EMG) activity during sleep in patients with craniofacial pain (n = 63) or no painful conditions (n = 52) and between patients with tension-type headache (TTH: n = 30) and healthy control individuals (n = 30). All participants used a portable single-channel EMG device (Medotech A/S) for four nights. There was no significant difference in EMG activity between craniofacial pain (24.5 ± 17.9 events/hr) and no painful conditions (19.7 ± 14.5), or between TTH (20.8 ± 15.0) and healthy control individuals (15.2 ± 11.6, p >.050). There were positive correlations between EMG activity and number of painful muscles (r = 0.188; p = 0.044), characteristic pain intensity (r = 0.187; p = 0.046), McGill Pain Questionnaire (r = 0.251; p = 0.008), and depression scores (r = 0.291; p = 0.002). Patients with painful conditions had significantly higher night-to-night variability compared with pain-free individuals (p craniofacial pain conditions and pain-free individuals in terms of jaw-muscle EMG activity recorded with a single-channel EMG device during sleep. However, some associations may exist between the level of EMG activity and various parameters of craniofacial pain. Longitudinal studies are warranted to further explore the relationship between sleep bruxism and craniofacial pain.

  9. Effect of tongue position on masseter and temporalis electromyographic activity during swallowing and maximal voluntary clenching: a cross-sectional study.

    Science.gov (United States)

    Valdés, C; Astaburuaga, F; Falace, D; Ramirez, V; Manns, A

    2014-12-01

    The purpose of this study was to measure and compare the tonic electromyographic (EMG) activity of the temporalis and masseter muscles following placement of the tongue either on the palate or in the floor of the mouth during swallowing and maximal voluntary clenching (MVC). Thirty healthy dental students with natural dentition and bilateral molar support, between the ages of 18 and 22, with no prior history of oro-facial injury, or current or past pain in the jaw, mouth or tongue participated in the study. Tonic masseter and temporalis EMG activities were recorded using surface electrodes. Subjects were instructed to passively place the tongue either on the anterior hard palate or in the floor of the mouth during swallowing and MVC. At each tongue position, the resulting EMG was recorded. During swallowing, no significant difference in EMG activity was found either for the masseter (P-value = 0.1592) or the temporalis (P-value = 0.0546) muscles, regardless of the tongue position. During MVC, there was a statistically significant difference for both the masseter (P-value = 0.0016) and the temporalis (P-value = 0.0277) muscles with lower levels recorded with the tongue in the floor of the mouth. This study found that in normal, pain-free subjects, placing the tongue in the floor of the mouth significantly reduces masticatory muscle activity during MVC. Thus, it may be considered as a possible therapeutic option to decrease masticatory muscle activity; however, further research is needed in patients with oro-facial pain.

  10. Induction and modulation of referred muscle pain in humans

    DEFF Research Database (Denmark)

    Laursen, René Johannes

    afferents. Furthermore, cutaneous anesthesia of the RP area resulted in a reduction of RP intensity of 22%, while a complete nerve block of afferents from the RP area resulted in a 40% reduction. In summary, observations from the presented experiments suggest that elicitation of referred muscle pain...... are needed. Spinal cord and higher centers are likely structures to study. The data presented in this thesis have made further contributions to understanding the mechanisms of muscle pain and RP that can be helpful in diagnosis, control, and treatment of muscle pain. Moreover, the intramuscular, electrical...

  11. Characteristics of Myofascial Pain Syndrome of the Infraspinatus Muscle.

    Science.gov (United States)

    Kwon, Junbeom; Kim, Hyoung Seop; Chang, Won Hyuk; Park, Chunung; Lee, Sang Chul

    2017-08-01

    To report the characteristics of myofascial trigger points (MTrPs) in the infraspinatus muscle and evaluate the therapeutic effect of trigger-point injections. Medical records of 297 patients (221 women; age, 53.9±11.3 years) with MTrPs in the infraspinatus muscle were reviewed retrospectively. Because there were 83 patients with MTrPs in both infraspinatus muscles, the characteristics of total 380 infraspinatus muscles with MTrPs (214 one side, 83 both sides) were investigated. Specific characteristics collected included chief complaint area, referred pain pattern, the number of local twitch responses, and distribution of MTrPs in the muscle. For statistical analysis, the paired t-test was used to compare a visual analogue scale (VAS) before and 2 weeks after the first injection. The most common chief complaint area of MTrPs in the infraspinatus muscle was the scapular area. The most common pattern of referred pain was the anterolateral aspect of the arm (above the elbow). Active MTrPs were multiple rather than single in the infraspinatus muscle. MTrPs were frequently in the center of the muscle. Trigger-point injection of the infraspinatus muscle significantly decreased the pain intensity. Mean VAS score decreased significantly after the first injection compared to the baseline (7.11 vs. 3.74; pmyofascial pain syndrome of the infraspinatus muscle.

  12. APPLICATION OF MRI IN THE DIAGNOSTICS OF M. MASSETER

    Directory of Open Access Journals (Sweden)

    Mariana Dimova-Gabrovska

    2017-06-01

    Full Text Available Magnetic resonance imaging (MRI is a non-invasive diagnostic method which can provide detailed images of organs and structures of the human body. The purpose of this review is to explore and introduce the diagnostic capabilities of MRI in imaging m. masseter in conditions of norm and pathology. The material of the review is information of 20 literary sources selected from 530, found by keywordsfromJanuary to April 2017. The information about MRI imaging of the normal anatomy of m. masseter and the most common findings in muscle - muscle hypertrophy, inflammatory changes, vascular malformations, intramuscular hemangioma, cysticercosis and changes after radiotherapy was analyzed. In conclusion, the diagnostic capabilities of MRI of masseter muscle – both in the conditions of norm and pathology were confirmed. The method is considered to be reliable, objective, non-invasive and accurate.

  13. Mucosal versus muscle pain sensitivity in provoked vestibulodynia

    Directory of Open Access Journals (Sweden)

    Witzeman K

    2015-08-01

    Full Text Available Kathryn Witzeman,1 Ruby HN Nguyen,2 Alisa Eanes,3 Sawsan As-Sanie,4 Denniz Zolnoun51Department of Obstetrics and Gynecology, Denver Health Medical Center, Denver, CO, 2Division of Epidemiology and Community Health, University of Minnesota, Minneapolis, MN, 3Pelvic Pain Research Unit, Division of Advanced Laparoscopy and Pelvic Pain, Department of Obstetrics and Gynecology, University of North Carolina School of Medicine, Chapel Hill, NC, 4Department of Obstetrics and Gynecology, Division of Minimally Invasive Gynecologic Surgery, University of Michigan, Ann Arbor, MI, 5Department of Obstetrics and Gynecology and Center for Neurosensory Disorders, University of North Carolina, Chapel Hill, NC, USABackground: An estimated 8.3%–16% of women experience vulvovaginal discomfort during their lifetime. Frequently these patients report provoked pain on contact or with attempted intercourse, commonly referred to as provoked vestibulodynia (PVD. Despite the burden of this condition, little is known about its potential etiologies including pelvic floor muscular dysfunction and mucosal components. This knowledge would be beneficial in developing targeted therapies including physical therapy.Objective: To explore the relative contribution of mucosal versus muscle pain sensitivity on pain report from intercourse among women with PVD.Design: In this proof of concept study, 54 women with PVD underwent a structured examination assessing mucosal and pelvic muscle sensitivity.Methods: We examined three mucosal sites in the upper and lower vestibule. Patients were asked to rate their pain on cotton swab palpation of the mucosa using a 10-point visual analog scale. Muscle pain was assessed using transvaginal application of pressure on right and left puborectalis, and the perineal muscle complex. The Gracely pain scale (0–100 was used to assess the severity of pain with intercourse, with women rating the lowest, average, and highest pain levels; a 100 rating the

  14. Referred muscle pain/hyperalgesia and central sensitisation.

    Science.gov (United States)

    Giamberardino, Maria Adele

    2003-05-01

    Referred muscle pain, resulting from algogenic conditions in viscera or other deep somatic structures (another muscle, a joint), is most often accompanied by secondary hyperalgesia and trophic changes (hypotrophy). Referred pain/ hyperalgesia from viscera is partly due to central sensitisation of viscero-somatic convergent neurons (triggered by the massive afferent visceral barrage) but also probably results from a reflex arc activation (the visceral input triggers reflex muscle contraction in turn responsible for sensitisation of muscle nociceptors). Referred pain/hyperalgesia from deep somatic structures is not explained by the mechanism of central sensitisation of convergent neurons in its original form, since there is little,convergence from deep tissues in the dorsal horn neurons. It has been proposed that these connections, not present from the beginning, are opened by nociceptive input from skeletal muscle, and that referral to myotomes outside the lesion results from the spread of central sensitisation to adjacent spinal segments.

  15. Modelling relative masseter force from surface electromyograms during mastication in non-human primates.

    Science.gov (United States)

    Hylander, W L; Johnson, K R

    1993-03-01

    The purpose was to analyse the relation between masseter electromyograms (EMGs) and relative masseter force during the power stroke of mastication. The electromyographic activity of the masseter was characterized by recording from bipolar surface electrodes placed over the superficial portion of the muscle; relative masseter force was estimated by characterizing surface bone strain along the lateral aspect of the zygomatic arch. The subjects were six adult macaques and one adult baboon. Masseter EMGs were quantified by r.m.s. analysis of the raw digitized EMG. The length of the time interval (the time constant) during which the r.m.s. values were calculated was repeatedly altered so as to determine which time constant was optimal for producing an EMG-derived waveform that best mimicked relative masseter force during the near-isometric phase of muscle contraction. The data indicate that between subjects this time constant varied from 35 to 72 ms, with an overall median of 42 ms and a grand mean of 49 ms. The use of a 42-ms time constant for all of the subjects resulted in an average latency between the masseter EMG waveform and relative masseter force of about 30 ms during the latter portion of the power stroke of mastication. This analysis provides, as a first approximation, an empirical basis for modelling relative jaw-muscle force using surface EMGs recorded during that portion of the power stroke of mastication when the jaw-closing muscles are contracting under near isometric conditions.

  16. The effect of culture on pain sensitivity.

    Science.gov (United States)

    Al-Harthy, M; Ohrbach, R; Michelotti, A; List, T

    2016-02-01

    Cross-cultural differences in pain sensitivity have been identified in pain-free subjects as well as in chronic pain patients. The aim was to assess the impact of culture on psychophysical measures using mechanical and electrical stimuli in patients with temporomandibular disorder (TMD) pain and pain-free matched controls in three cultures. This case-control study compared 122 female cases of chronic TMD pain (39 Saudis, 41 Swedes and 42 Italians) with equal numbers of age- and gender-matched TMD-free controls. Pressure pain threshold (PPT) and tolerance (PPTo) were measured over one hand and two masticatory muscles. Electrical perception threshold and electrical pain threshold (EPT) and tolerance (EPTo) were recorded between the thumb and index fingers. Italian females reported significantly lower PPT in the masseter muscle than other cultures (P cultures (P = 0.017). Italians reported significantly lower PPTo in all muscles than Swedes (P ≤ 0.006) and in the masseter muscle than Saudis (P cultures (P = 0.01). Temporomandibular disorder cases, compared to TMD-free controls, reported lower PPT and PPTo in all the three muscles (P cultural differences between groups in the PPT, PPTo and EPTo. Overall, Italian females reported the highest sensitivity to both mechanical and electrical stimulation, while Swedes reported the lowest sensitivity. Mechanical pain thresholds differed more across cultures than did electrical pain thresholds. Cultural factors may influence response to type of pain test.

  17. Experimental quadriceps muscle pain impairs knee joint control during walking

    DEFF Research Database (Denmark)

    Henriksen, Marius; Alkjaer, Tine; Lund, Hans

    2007-01-01

    of the quadriceps muscle, resulting in impaired knee joint control and joint instability during walking. The changes are similar to those observed in patients with knee pain. The loss of joint control during and after pain may leave the knee joint prone to injury and potentially participate in the chronicity...

  18. Pain Recognition using Spatiotemporal Oriented Energy of Facial Muscles

    DEFF Research Database (Denmark)

    Irani, Ramin; Nasrollahi, Kamal; Moeslund, Thomas B.

    2015-01-01

    Pain is a critical sign in many medical situations and its automatic detection and recognition using computer vision techniques is of great importance. Utilizes this fact that pain is a spatiotemporal process, the proposed system in this paper employs steerable and separable filters to measures e...... energies released by the facial muscles during the pain process. The proposed system not only detects the pain but recognizes its level. Experimental results on the publicly available pain database of UNBC show promising outcome for automatic pain detection and recognition.......Pain is a critical sign in many medical situations and its automatic detection and recognition using computer vision techniques is of great importance. Utilizes this fact that pain is a spatiotemporal process, the proposed system in this paper employs steerable and separable filters to measures...

  19. Exercise-induced muscle pain, soreness, and cramps.

    Science.gov (United States)

    Miles, M P; Clarkson, P M

    1994-09-01

    The three types of pain related to exercise are 1) pain experienced during or immediately following exercise, 2) delayed onset muscle soreness, and 3) pain induced by muscle cramps. Each is characterized by a different time course and different etiology. Pain perceived during exercise is considered to result from a combination of factors including acids, ions, proteins, and hormones. Although it is commonly believed that lactic acid is responsible for this pain, evidence suggests that it is not the only factor. However, no single factor has ever been identified. Delayed onset muscle soreness develops 24-48 hours after strenuous exercise biased toward eccentric (muscle lengthening) muscle actions or strenuous endurance events like a marathon. Soreness is accompanied by a prolonged strength loss, a reduced range of motion, and elevated levels of creatine kinase in the blood. These are taken as indirect indicators of muscle damage, and biopsy analysis has documented damage to the contractile elements. The exact cause of the soreness response is not known but thought to involve an inflammatory reaction to the damage. Muscle cramps are sudden, intense, electrically active contractions elicited by motor neuron hyperexcitability. Although it is commonly assumed that cramps during exercise are the result of fluid electrolyte imbalance induced by sweating, two studies have not supported this. Moreover, participants in occupations that require chronic use of a muscle but do not elicit profuse sweating, such as musicians, often experience cramps. Fluid electrolyte imbalance may cause cramps if there is profuse prolonged sweating such as that found in working in a hot environment. Thus, despite the common occurrence of pain associated with exercise, the exact cause of these pains remains a mystery.

  20. Discussion for pain of shoulder muscles in badminton player

    OpenAIRE

    兒嶋, 昇; Kojima, Noboru; 升, 佑二郎; Masu, Yujiro; 野瀬, 朋洋; Nose, Tomohiro

    2013-01-01

    This study aimed to provide a basis for the development of appropriate preventive measures during training and coaching by examining shoulder impingement in Japanese top-level university badminton players. As the contracture of muscles, such as the anterior and middle scalene muscles, as well as the infraspinatus, was likely to cause pain, it may be effective to perform conditioning to reduce such muscle contracture during coaching in order to reduce the occurrence of impairment, and impro...

  1. Experimental Muscle Pain Impairs the Synergistic Modular Control of Neck Muscles.

    Directory of Open Access Journals (Sweden)

    Leonardo Gizzi

    Full Text Available A motor task can be performed via different patterns of muscle activation that show regularities that can be factorized in combinations of a reduced number of muscle groupings (also referred to as motor modules, or muscle synergies. In this study we evaluate whether an acute noxious stimulus induces a change in the way motor modules are combined to generate movement by neck muscles. The neck region was selected as it is a region with potentially high muscular redundancy. We used the motor modules framework to assess the redistribution of muscular activity of 12 muscles (6 per side in the neck region of 8 healthy individuals engaged in a head and neck aiming task, in non-painful conditions (baseline, isotonic saline injection, post pain and after the injection of hypertonic saline into the right splenius capitis muscle. The kinematics of the task was similar in the painful and control conditions. A general decrease of activity was noted for the injected muscle during the painful condition together with an increase or decrease of the activity of the other muscles. Subjects did not adopt shared control strategies (motor modules inter subject similarity at baseline 0.73±0.14; the motor modules recorded during the painful condition could not be used to reconstruct the activation patterns of the control conditions, and the painful stimulus triggered a subject-specific redistribution of muscular activation (i.e., in some subjects the activity of a given muscle increased, whereas in other subjects it decreased with pain. Alterations of afferent input (i.e., painful stimulus influenced motor control at a multi muscular level, but not kinematic output. These findings provide new insights into the motor adaptation to pain.

  2. Experimental Muscle Pain Impairs the Synergistic Modular Control of Neck Muscles.

    Science.gov (United States)

    Gizzi, Leonardo; Muceli, Silvia; Petzke, Frank; Falla, Deborah

    2015-01-01

    A motor task can be performed via different patterns of muscle activation that show regularities that can be factorized in combinations of a reduced number of muscle groupings (also referred to as motor modules, or muscle synergies). In this study we evaluate whether an acute noxious stimulus induces a change in the way motor modules are combined to generate movement by neck muscles. The neck region was selected as it is a region with potentially high muscular redundancy. We used the motor modules framework to assess the redistribution of muscular activity of 12 muscles (6 per side) in the neck region of 8 healthy individuals engaged in a head and neck aiming task, in non-painful conditions (baseline, isotonic saline injection, post pain) and after the injection of hypertonic saline into the right splenius capitis muscle. The kinematics of the task was similar in the painful and control conditions. A general decrease of activity was noted for the injected muscle during the painful condition together with an increase or decrease of the activity of the other muscles. Subjects did not adopt shared control strategies (motor modules inter subject similarity at baseline 0.73±0.14); the motor modules recorded during the painful condition could not be used to reconstruct the activation patterns of the control conditions, and the painful stimulus triggered a subject-specific redistribution of muscular activation (i.e., in some subjects the activity of a given muscle increased, whereas in other subjects it decreased with pain). Alterations of afferent input (i.e., painful stimulus) influenced motor control at a multi muscular level, but not kinematic output. These findings provide new insights into the motor adaptation to pain.

  3. [Neck pain due to tendonitis of the longus colli muscle].

    Science.gov (United States)

    Coebergh, Jan Adriaan; Koppen, Hille; van Gils, Ad P; de Bruijn, Bas F

    2010-01-01

    Two patients presented to Accidents and Emergency with severe neck pain: a 70-year-old woman with acute, severe neck pain, which had developed a few days after outpatient resection of her left lingual tonsil. The patient was suspected to have spondylodiscitis. The other patient, a 54-year-old woman, was referred with severe neck pain and suspected meningitis. In both women, the pain was diagnosed as acute calcifying tendonitis of the longus colli muscle. This benign condition can present to many different specialities. Both patients responded well to treatment with NSAIDs. Acute calcifying tendonitis of the longus colli muscle can be diagnosed using various imaging techniques, such as X-ray, CT or MRI imaging. Calcification on cervical CT or a high signal on T2-weighted MRI images of the longus colli muscle are pathognomonic of tendonitis. A correct diagnosis can prevent further invasive diagnostics and/or unnecessary treatment.

  4. Knee Muscle Forces during Walking and Running in Patellofemoral Pain Patients and Pain-Free Controls

    Science.gov (United States)

    Besier, Thor F.; Fredericson, Michael; Gold, Garry E.; Beaupré, Gary S.; Delp, Scott L.

    2009-01-01

    One proposed mechanism of patellofemoral pain, increased stress in the joint, is dependent on forces generated by the quadriceps muscles. Describing causal relationships between muscle forces, tissue stresses, and pain is difficult due to the inability to directly measure these variables in vivo. The purpose of this study was to estimate quadriceps forces during walking and running in a group of male and female patients with patellofemoral pain (n=27, 16 female; 11 male) and compare these to pain-free controls (n=16, 8 female; 8 male). Subjects walked and ran at self-selected speeds in a gait laboratory. Lower limb kinematics and electromyography (EMG) data were input to an EMG-driven musculoskeletal model of the knee, which was scaled and calibrated to each individual to estimate forces in 10 muscles surrounding the joint. Compared to controls, the patellofemoral pain group had greater co-contraction of quadriceps and hamstrings (p=0.025) and greater normalized muscle forces during walking, even though the net knee moment was similar between groups. Muscle forces during running were similar between groups, but the net knee extension moment was less in the patellofemoral pain group compared to controls. Females displayed 30-50% greater normalized hamstring and gastrocnemius muscle forces during both walking and running compared to males (pjoint contact forces and joint stresses than pain-free subjects. PMID:19268945

  5. Electromyography in evaluation of pain after different types of tonsillectomy: prospective randomized study.

    Science.gov (United States)

    Vaiman, Michael; Gavrieli, Haim; Krakovski, Daniel

    2007-01-01

    Combined surface electromyography (sEMG) and visual analogue scale (VAS) pain assessment was performed on randomly assigned adults following tonsillectomy to research the effect of fibrin sealant (Group 1, n = 25), CO(2) laser (Group 2, n = 18) and electrocoagulation (Group 3, n = 40) on postsurgical pain. Timing and amplitude of sEMG activity of masseter, infrahyoid and submandibular muscles were measured during swallowing simultaneously with VAS assessment and compared to normative database. Postsurgical electric activity of masseter and infrahyoid was significantly higher in comparison with normative database. sEMG and VAS data showed that tonsillectomy ended with fibrin sealant caused less pain than laser or electrocoagulation techniques with no correlation between the VAS score and duration of swallows. Tonsillectomy affects muscle activity significantly by involving additional muscles (infrahyoid) in swallowing. Combined sEMG and VAS data indicated electrocautery as the most painful, laser as less painful, and fibrin sealant as the least painful technique.

  6. Experimental neck muscle pain impairs standing balance in humans

    CERN Document Server

    Vuillerme, Nicolas; 10.1007/s00221-008-1639-7

    2009-01-01

    Impaired postural control has been reported in patients with chronic neck pain of both traumatic and non-traumatic etiologies, but whether painful stimulation of neck muscle per se can affect balance control during quiet standing in humans remains unclear. The purpose of the present experiment was thus to investigate the effect of experimental neck muscle pain on standing balance in young healthy adults. To achieve this goal, 16 male university students were asked to stand upright as still as possible on a force platform with their eyes closed in two conditions of No pain and Pain of the neck muscles elicited by experimental painful electrical stimulation. Postural control and postural performance were assessed by the displacements of the center of foot pressure (CoP) and of the center of mass (CoM), respectively. The results showed increased CoP and CoM displacements variance, range, mean velocity, and mean and median frequencies in the Pain relative to the No pain condition. The present findings emphasize t...

  7. Is back pain during childhood or adolescence associated with muscle strength, muscle endurance or aerobic capacity

    DEFF Research Database (Denmark)

    Lardon, Arnaud; Leboeuf-Yde, Charlotte; Le Scanff, Christine

    2015-01-01

    BACKGROUND: Back pain is a common condition during childhood and adolescence. The causes of back pain are largely unknown but it seems plausible that some physical factors such as back muscle strength, back muscle endurance and aerobic capacity may play a role in its development, in particular...... in the early years. OBJECTIVES: The objectives of this review were to investigate in childhood and adolescence 1) if muscular strength in trunk extension is associated with back pain, 2) if muscular endurance in trunk extension is associated with back pain and 3) if aerobic capacity is associated with back...

  8. Observations on muscle pain in man, with particular reference to pain during needle electromyography.

    Science.gov (United States)

    Meadows, J C

    1970-08-01

    Muscle pain receptors have been studied in man. During the advance of an EMG needle pain is most regularly experienced as the muscle fascia is pierced. Further advancing the needle is usually quite painless. However, there are scantily distributed points within the muscle (`pain spots') which may give rise to pain if encountered by the advancing needle. The nature of the responsible receptors is obscure but it is likely that pain may sometimes be caused by activation of nerve fibres (presumably from these receptors) coursing through the muscle rather than by activation of the receptors themselves. Intramuscular bleeding is unlikely to contribute often to the pain of needle electromyography. Mechanically sensitive `pain spots' are more painful than other areas when stimulated electrically or injected with hypertonic (6%) saline. This suggests a common receptor. The high electrical threshold and relative invulnerability to pressure of afferent fibres from these receptors suggest that they are mainly of small diameter. These findings are discussed in relation to experimental work on pressure-pain receptors in animals.

  9. Muscle activation patterns in posttraumatic neck pain

    NARCIS (Netherlands)

    Nederhand, Marcus Johannes

    2003-01-01

    As an important consequence of our research, we question the relevance of the criteria of the WAD injury severity classification system. We showed that the musculoskeletal signs in WAD grade II are not characterized by muscle spasm, (i.e. increase of muscle activity), but rather by a decrease in mus

  10. 牙尖交错位最大紧咬时胸锁乳突肌与咬肌肌电研究%Electromyographic activity of the masseter and sternocleidomastoid muscle during maximal voluntary clenching in intercuspal position

    Institute of Scientific and Technical Information of China (English)

    郭少雄; 李宝勇; 张渊; 刘璐; 邓琪; 王美青

    2015-01-01

    Objective :To investigate the relationship between occlusal force level and the surface electro‐myography(SEMG) activity of sternocleidomastoid muscle (SCM )versus masseter muscle(MM ) during maximal voluntary clenching (MVC) in intercuspal position(ICP) .Methods :T‐Scan III system and BioEMG III system were used to record SEMG activity of the SCM and of the MM simultaneously .Recordings which were obtained from 25 healthy young adult during MVC were analyzed in different occlusal force levels .Normalized SEMG value was ratio of SEMG values of different occlusal force levels to MVC .Results :There was no difference between bite force , SEMG value of left side and right side in ICP‐MVC .Ratios of sternocleidomastoid(SCM ) to masseter muscle activity range from (9 .13 ± 4 .77)% to(10 .23 ± 6 .47)% .In normalized SEMG value of the MM and SCM ,which increased before 75% ‐MVC ,and decreased after 75% ‐ICP(P< 0 .05) .Conclusion :The results confirmed that a lower SEMG activity of SCM is similar to MM when the highest level of bite force achieved during MVC in ICP .%目的:以咬肌(Masseter muscle ,MM )为对照,研究牙尖交错位最大紧咬过程中咬合力和胸锁乳突肌(Sternocleidomastoid muscle ,SCM )肌电之间的关系。方法:采用 T‐scanIII 咬合记录仪和 BioEMG III 肌电图仪,同步记录25名健康受试者 SCM 和 MM 的肌电值,分析不同咬合力水平下肌电值与自主最大紧咬(Maximal voluntary clenching ,MVC)时肌电值的比值的变化。结果:M VC 时,咬合力、SCM 及 MM 肌电值双侧之间无明显差异,SCM 肌电幅值约为 MM 的(9.13±4.77)%~(10.23±6.47)%,SCM 及 MM 的肌电比值在达到最大咬合力的75%之前均呈逐渐增高趋势,但从该水平至 MVC 时均显著下降(P< 0.05)。结论:在自主最大紧咬过程中 SCM 表现出与 MM 同步的先升高后降低的肌电变化规律。

  11. Altered pain sensitivity and axioscapular muscle activity in neck pain patients compared with healthy controls

    DEFF Research Database (Denmark)

    Christensen, Steffan Wittrup; Hirata, Rogerio Pessoto; Graven-Nielsen, Thomas

    2017-01-01

    from eight bilateral muscles. The first and last three series were separated by 8 min and 42 s, respectively. Each series consisted of three slow and three fast movements. Pressure pain thresholds (PPTs) were recorded bilaterally from neck, head and arm at baseline, after the third and sixth movement...... series. Pain intensity was recorded on an electronic visual analogue scale (VAS). RESULTS: Larger pain areas and higher VAS scores were found in patients compared with controls (p PPTs were lower in patients...

  12. Muscle activity pattern dependent pain development and alleviation

    DEFF Research Database (Denmark)

    Sjøgaard, Gisela; Søgaard, Karen

    2014-01-01

    during physical activities at leisure and sport the motor recruitment patterns are more dynamic including regularly relatively high muscle forces - also activating type 2 muscles fibers - as well as periods of full relaxation even of the type 1 muscle fibers. Such activity is unrelated to muscle pain......Muscle activity is for decades considered to provide health benefits irrespectively of the muscle activity pattern performed and whether it is during e.g. sports, transportation, or occupational work tasks. Accordingly, the international recommendations for public health-promoting physical activity...... do not distinguish between occupational and leisure time physical activity. However, in this body of literature, attention has not been paid to the extensive documentation on occupational physical activity imposing a risk of impairment of health - in particular musculoskeletal health in terms...

  13. Medicines to Treat Muscle Spasms and Pain

    Science.gov (United States)

    ... Reports recommends methocarbamoI or chlorzoxazone . For muscle spasticity :  Baclofen If baclofen does not work well for you, then Consumer Reports recommends tizanidine . Cyclobenzaprine and baclofen are both prescription medicines. Cyclobenzaprine costs $8 to $ ...

  14. 不同开口度对大鼠咬肌及颞下颌关节的影响%Effects of mouth opening degree on masseter muscle and temporomandibular joint of rats

    Institute of Scientific and Technical Information of China (English)

    党薇; 于世宾; 何惠明; 李甜

    2013-01-01

    目的:观察不同开口度对大鼠咬肌及颞下颌关节的影响,探索实验操作过程中大鼠最适张口度.方法:选择头部发育完全的12周龄雄性SD大鼠25只,随机分为1个对照组和4个实验组(每组5只),分别给予不同开口度处理.所有大鼠经麻醉后除对照组(开口度0 mm)外,4个实验组分别给予10、15、20、25 mm不同开口度的被动张口干预.每天干预1次,每次0.5h,连续7d.干预期间,每天观察并记录各大鼠的体质量变化情况.连续处理7d后处死大鼠,完整取出大鼠颞下颌关节及咬肌,常规组织学观察.结果:10、15、20 mm组与对照组相比,大鼠体质量、颞下颌关节及咬肌组织等结构均无明显差别;而25mm组大鼠体质量增长缓慢,从干预后第2天起各时间点的体质量均明显低于对照组和其他实验组,差异有统计学意义(P<0.05);而且咬肌肌纤维间有红细胞渗出和炎症细胞聚集;颞下颌关节髁突大量软骨细胞增殖,髁突软骨厚度明显增加.结论:大鼠开口度达到25 mm,并持续0.5h连续7d时,会引起其咬肌及颞下颌关节显微结构的变化.%AIM: To investigate the effects of mouth opening degree on masseter muscle and temporoman dibular joint in rats so as to find out the most suitable degree of mouth opening in experimental procedures. METHODS: 25 male SD rats aged 12 weeks were randomly divided into 5 groups(n =5). After anesthesia the rats were intervened with different degrees of passive mouth opening (10 mm, 15 mm, 20 mm and 25 mm) for 0. 5 h a day. The control rats received no intervention. Body weight of the rats was recorded during the intervention period. After 7 days of intervention, all rats were sacrificed, the masseter muscles and the temporomandibular joints were taken and examined by histology. RESULTS: No significant change was found among the 10 mm, 15 mm and 20 mm groups and the control group in terms of body weight and histological feature (P>0

  15. Uso de toxina botulínica para tratamiento de la hipertrofía del músculo masetero Use of botulinum toxin for treatment of hypetrophy of the masseter muscle

    Directory of Open Access Journals (Sweden)

    F. González Magaña

    2012-09-01

    Full Text Available Definimos la hipertrofia del músculo masetero como el crecimiento excesivo de la masa muscular de dicho músculo, de presentación subclínica y de etiología multifactorial. Presenta una incidencia entre los 20 a 40 años sin predilección de sexo. Desde que en 1880 Legg la describiera por primera vez, se han intentado múltiples tratamientos, desde los médicos hasta los quirúrgicos, siendo el tratamiento con toxina botulínica el de mayor aceptación en la actualidad. El objetivo del presente artículo es realizar una revisión bibliográfica y proveer una herramienta para el médico que se enfrente a la hipertrofia del músculo masetero, además de presentar un caso clínico unilateral y la técnica empleada para su tratamiento. Como método diagnóstico en el paciente empleamos TAC de cráneo y macizo facial con cortes finos a 1 mm, así como de la región maseterina y aplicamos toxina botulínica de acuerdo a la zona de seguridad propuesta por Nam-Ho Kim y en base a los puntos anatómicos que indica el mismo protocolo, a dosis de 50 U en intervalos de 3 meses. Empleamos también TAC postoperatorio como medio de evaluación del resultado. Los tratamientos médicos con toxina botulínica son variables en sus dosis, aplicaciones y técnicas, así como en los diferentes productos disponibles en el mercado. En nuestro caso, el resultado fue clínicamente satisfactorio, cubriendo en su totalidad las expectativas del paciente. Proponemos que la protocolización del paciente, las dosis adecuadas, el tiempo entre aplicaciones y los sitios anatómicos correctos de inyección, llevan a la corrección de la hipertrofia del músculo masetero.Masseter muscle hypertrophy is an overgrowth of muscle mass with subclinical presentation and multifactorial etiology, with an incidence between 20 to 40 years and without sex predilection. In 1880 Legg describes this pathology for the first time and since then have been reported and attempted to formally

  16. Muscle activation during selected strength exercises in women with chronic neck muscle pain

    DEFF Research Database (Denmark)

    Andersen, L.L.; Kjaer, M.; Andersen, C.H.

    2008-01-01

    ) (luring selected strengthening exercises in women undergoing rehabilitation for chronic neck muscle pain (defined as a clinical diagnosis of trapezins myalgia). Subjects. The subjects were 12 female workers (age = 30-60 years) with a clinical diagnosis of trapezius myalgia and a mean baseline pain...

  17. Muscle activation during selected strength exercises in women with chronic neck muscle pain

    DEFF Research Database (Denmark)

    Andersen, Lars L; Kjaer, Michael; Andersen, Christoffer H

    2008-01-01

    selected strengthening exercises in women undergoing rehabilitation for chronic neck muscle pain (defined as a clinical diagnosis of trapezius myalgia). SUBJECTS: The subjects were 12 female workers (age=30-60 years) with a clinical diagnosis of trapezius myalgia and a mean baseline pain intensity of 5...

  18. Experimental tooth clenching. A model for studying mechanisms of muscle pain.

    Science.gov (United States)

    Dawson, Andreas

    2013-01-01

    The overall goal of this thesis was to broaden knowledge of pain mechanisms in myofascial temporomandibular disorders (M-TMD). The specific aims were to: Develop a quality assessment tool for experimental bruxism studies (study I). Investigate proprioceptive allodynia after experimental tooth clenching exercises (study II). Evaluate the release of serotonin (5-HT), glutamate, pyruvate, and lactate in healthy subjects (study III) and in patients with M-TMD (study IV), after experimental tooth clenching exercises. In (I), tool development comprised 5 steps: (i) preliminary decisions, (ii) item generation, (iii) face-validity assessment, (iv) reliability and discriminative validity testing, and (v) instrument refinement. After preliminary decisions and a literature review, a list of 52 items to be considered for inclusion in the tool was generated. Eleven experts were invited to participate on the Delphi panel, of which 10 agreed. After four Delphi rounds, 8 items remained and were included in the Quality Assessment Tool for Experimental Bruxism Studies (Qu-ATEBS). Inter-observer reliability was acceptable (k = 0.77), and discriminative validity high (phi coefficient 0.79; P tooth clenching task with a clenching level of 10%, 20%, or 40% of maximal voluntary clenching force (MVCF). Pain intensity, fatigue, perceived intensity of vibration (PIV), perceived discomfort (PD), and pressure pain threshold (PPT) were measured throughout. A significant increase in pain intensity and fatigue but not in PD was observed over time. A significant increase in PIV was only observed at 40 min, and PPT decreased significantly over time at 50 and 60 min compared to baseline. In (III), 30 healthy subjects (16 females, and 14 males) participated in two sessions at a minimum interval of 1 wk. Microdialysis was done to collect 5-HT, glutamate, pyruvate, and lactate and to measure masseter muscle blood flow. Two hours after the start of microdialysis, participants were randomized to a 20

  19. Kinesiophobia, Pain, Muscle Functions, and Functional Performances among Older Persons with Low Back Pain

    Directory of Open Access Journals (Sweden)

    Nor Azizah Ishak

    2017-01-01

    Full Text Available Objectives. This study aims (1 to determine the association between kinesiophobia and pain, muscle functions, and functional performances and (2 to determine whether kinesiophobia predicts pain, muscle functions, and functional performance among older persons with low back pain (LBP. Methods. This is a correlational study, involving 63 institutionalized older persons (age = 70.98±7.90 years diagnosed with LBP. Anthropometric characteristics (BMI and functional performances (lower limb function, balance and mobility, and hand grip strength were measured. Muscle strength (abdominal and back muscle strength was assessed using the Baseline® Mechanical Push/Pull Dynamometer, while muscle control (transverse abdominus and multifidus was measured by using the Pressure Biofeedback Unit. The pain intensity and the level of kinesiophobia were measured using Numerical Rating Scale and Tampa Scale of Kinesiophobia, respectively. Data were analyzed using Pearson’s correlation coefficients and multivariate linear regressions. Results. No significant correlations were found between kinesiophobia and pain and muscle functions (all p>0.05. Kinesiophobia was significantly correlated with mobility and balance (p=0.038, r=0.263. Regressions analysis showed that kinesiophobia was a significant predictor of mobility and balance (p=0.038. Conclusion. We can conclude that kinesiophobia predicted mobility and balance in older persons with LBP. Kinesiophobia should be continuously assessed in clinical settings to recognize the obstacles that may affect patient’s compliance towards a rehabilitation program in older persons with LBP.

  20. Pain-evoked trunk muscle activity changes during fatigue and DOMS

    DEFF Research Database (Denmark)

    Larsen, Lars Henrik; Hirata, Rogerio Pessoto; Graven-Nielsen, Thomas

    2017-01-01

    abdominal and back muscles. RESULTS: In DOMS, peak VAS scores were higher during bilateral control and bilateral saline-induced pain than fatigue (p ...-perturbation Delta-RMS-EMG in back muscles was higher during bilateral pain and lower during unilateral pain (p abdominal Delta-RMS-EMG was not significantly affected. CONCLUSION: Facilitated and attenuated back muscle responses to surface perturbations in bilateral and unilateral LBP, respectively......BACKGROUND: Muscle pain may reorganize trunk muscle activity but interactions with exercise-related muscle fatigue and delayed onset muscle soreness (DOMS) is to be clarified. METHODS: In 19 healthy participants, the trunk muscle activity during 20 multi-directional unpredictable surface...

  1. Effect of hypnosis on masseter EMG recorded during the 'resting' and a slightly open jaw posture.

    Science.gov (United States)

    Al-Enaizan, N; Davey, K J; Lyons, M F; Cadden, S W

    2015-11-01

    The aim of this experimental study was to determine whether minimal levels of electromyographic activity in the masseter muscle are altered when individuals are in a verified hypnotic state. Experiments were performed on 17 volunteer subjects (8 male, 9 female) all of whom gave informed consent. The subjects were dentate and had no symptoms of pain or masticatory dysfunction. Surface electromyograms (EMGs) were made from the masseter muscles and quantified by integration following full-wave rectification and averaging. The EMGs were obtained (i) with the mandible in 'resting' posture; (ii) with the mandible voluntarily lowered (but with the lips closed); (iii) during maximum voluntary clenching (MVC). The first two recordings were made before, during and after the subjects were in a hypnotic state. Susceptibility to hypnosis was assessed with Spiegel's eye-roll test, and the existence of the hypnotic state was verified by changes in ventilatory pattern. On average, EMG levels expressed as percentages of MVC were less: (i) when the jaw was deliberately lowered as opposed to being in the postural position: (ii) during hypnosis compared with during the pre- and post-hypnotic periods. However, analysis of variance followed by post hoc tests with multiple comparison corrections (Bonferroni) revealed that only the differences between the level during hypnosis and those before and after hypnosis were statistically significant (P hypnosis, it appears that part of that EMG is of biological origin.

  2. Effectiveness of core muscle strengthening for improving pain and dynamic balance among female patients with patellofemoral pain syndrome

    OpenAIRE

    2016-01-01

    [Purpose] Patellofemoral pain syndrome is a frequent musculoskeletal disorder, which can result from core muscles instability that can lead to pain and altered dynamic balance. The objective of this study is to assess the effect of core muscle strengthening on pain and dynamic balance in female patients with patellofemoral pain syndrome. [Subjects and Methods] Twenty female patients with age ranging from 16 to 40 years with patellofemoral pain syndrome were divided into study (N=10) and contr...

  3. Effects of NGF-induced muscle sensitization on proprioception and nociception.

    Science.gov (United States)

    Svensson, Peter; Wang, Kelun; Arendt-Nielsen, Lars; Cairns, Brian E

    2008-07-01

    Temporomandibular disorders (TMDs) are associated with perturbation of proprioceptive and nociceptive function. Recent studies have shown that injection of the neurotrophic protein nerve growth factor (NGF) into the masseter muscle causes sensitization to mechanical pressure stimuli; however, it is not clear if vibration sense and jaw stretch reflexes as measures of proprioceptive function as well as glutamate-evoked pain are also altered. We tested the hypothesis that NGF-induced mechanical sensitization would be associated with changes in vibration sense and stretch reflex sensitivity as well as facilitation of glutamate-evoked pain responses. A double-blind, randomized and placebo-controlled study was conducted on 14 healthy men. In one session subjects received an injection of NGF (5 microg in 0.2 ml) into the masseter muscle and in a control session an injection of buffered isotonic saline (0.9%, 0.2 ml). Subjects assessed their pain intensity on a 0-10 cm visual analogue scale (VAS) for 15 min after the injections. Pressure pain thresholds (PPT), vibration sense and jaw stretch reflexes were recorded at baseline and 1, 2, 3 and 24 h post-injection. The sensitivity to injections of glutamate into the masseter muscle (1 M, 0.2 ml) was assessed after 24 h. ANOVAs were used to assess significant differences. NGF did not cause more pain than isotonic saline, but significantly reduced PPTs 1, 2, 3 and 24 h post-injection (P affected by the NGF-induced sensitization; however, after glutamate injection a significant increase in the stretch reflex was observed in the injected masseter muscle in both sessions (P = 0.002). There were no significant differences in the perceived pain intensity of the glutamate injection between the masseter muscle pretreated with NGF or control (P > 0.414), although the glutamate-evoked pain drawing areas were larger for the NGF-pretreated masseter muscle (P = 0.009). In conclusion, this study confirms that masseter muscle injection of

  4. The effect of fear of movement on muscle activation in posttraumatic neck pain disability

    NARCIS (Netherlands)

    Nederhand, Marc J.; Hermens, Hermie J.; IJzerman, Maarten J.; Groothuis, Karin G.M.; Turk, Dennis C.

    2006-01-01

    Studies using surface electromyography have demonstrated a reorganization of muscle activation patterns of the neck and shoulder muscles in patients with posttraumatic neck pain disability. The neurophysiologically oriented "pain adaptation" model explains this reorganization as a useful adaptation

  5. Reorganized trunk muscle activity during multidirectional floor perturbations after experimental low back pain

    DEFF Research Database (Denmark)

    Larsen, Lars Henrik; Hirata, Rogerio Pessoto; Graven-Nielsen, Thomas

    2016-01-01

    each perturbation was extracted and averaged across perturbations. The difference (ΔRMS-EMG) and absolute difference (absolute ΔRMS-EMG) RMS from baseline conditions were extracted for each muscle during pain conditions and averaged bilaterally for back and abdominal muscle groups. Bilateral compared...... with unilateral pain induced higher VAS scores (P muscle activity during unilateral (P abdominal...... (P muscles during bilateral and decreased in the back (P abdominal (P muscles during unilateral pain. Bilateral pain caused greater absolute ΔRMS-EMG changes in the back (P abdominal (P muscle groups than unilateral pain. PERSPECTIVE: This study provided...

  6. Muscle impingement: MR imaging of a painful complication of osteochondromas

    Energy Technology Data Exchange (ETDEWEB)

    Uri, D.S. [Department of Radiology, Hospital of the University of Pennsylvania, 3400 Spruce Street, Philadelphia, PA 19104 (United States); Dalinka, M.K. [Department of Radiology, Hospital of the University of Pennsylvania, 3400 Spruce Street, Philadelphia, PA 19104 (United States); Kneeland, J.B. [Department of Radiology, Hospital of the University of Pennsylvania, 3400 Spruce Street, Philadelphia, PA 19104 (United States)

    1996-10-01

    The purpose of this study was to describe the magnetic resonance (MR) appearance of a newly recognized complication of osteochondromas. Two patients presented with pain and swelling over known osteochondromas. Plain radiographic studies were unrevealing. MR examinations were obtained to characterize the exostoses further and evaluate areas of palpable fullness. Increased signal was present in the muscles on T2-weighted images, which correlated with physical findings and was believed to represent muscle injury due to the osteochondroma. Pain and fullness may result from a number of osteochondroma-related complications, the most worrisome of which is malignant degeneration. Muscular impingement and injury should be considered in the differential diagnosis of pain and swelling in the region of an exostosis. MR imaging allows distinction of this entity, which may be radiographically occult and confused clinically with fracture, bursitis, or malignant degeneration. (orig.). With 2 figs.

  7. Experimental knee joint pain during strength training and muscle strength gain in healthy subjects

    DEFF Research Database (Denmark)

    Sørensen, T J; Langberg, Henning; Hodges, P W

    2012-01-01

    Knee joint pain and reduced quadriceps strength are cardinal symptoms in many knee pathologies. In people with painful knee pathologies, quadriceps exercise reduces pain, improves physical function, and increases muscle strength. A general assumption is that pain compromises muscle function...... and thus may prevent effective rehabilitation. This study evaluated the effects of experimental knee joint pain during quadriceps strength training on muscle strength gain in healthy individuals....

  8. Reconstruction of postoperative soft tissue defect of oral carcinoma using masseter muscle flap: Two cases report and literature review%嚼肌瓣整复口腔癌术后软组织缺损2例及文献回顾

    Institute of Scientific and Technical Information of China (English)

    黄平; 秦旭; 廖琳迪; 黄梅靖; 邵乐南; 陈卫民

    2012-01-01

    目的:总结应用嚼肌瓣修复口腔癌术后软组织缺损的临床效果.方法:收集2例口腔癌病例,利用嚼肌瓣修复术后软组织缺损,并对相关文献进行回顾.结果:口腔癌术后软组织缺损严重影响患者的口腔功能,应用嚼肌瓣以及生物膜整复可获得较为满意的功能及美学效果.结论:应用嚼肌瓣修复口腔癌术后软组织缺损可以获得较为满意的临床效果好.%Objective:To investigare feasibility the postoperative result of using masseter flap as a postoperative soft tissue defect of oral carcinoma reconstruction regional flap. Method: We choosed two cases of oral carcinoma patient, performing oral soft tissue defect reconstruction with masseter muscle flap, then make a briefly literature review. Result: Oral carcinoma is a kind of common head and neck cancer, and its postoperative soft tissue defect have severe impact on the oral function,such as eating, pronunciation, swallowing and so on. The using of split masseter muscle combined with oral biofilm could obtain satisfactory function and aesthetic effect in reconstruction of large area defect caused by the ablation of oral cancer. Conclusion: The masseter muscle can be used as a useful flap to reconstruct targe area oral cancer postoperative defect.

  9. The role of the free-way space in the generation of muscle pain among denture-wearers.

    Science.gov (United States)

    Monteith, B

    1984-09-01

    Although the myofascial pain dysfunction syndrome has a multiple aetiology, faulty vertical dimension is a frequent cause of muscular pain among wearers of full dentures. Furthermore, it has been found that the restoration of a physiological free-way space in such cases, using a method which is based upon cephalometric analysis of the gonial angle, often leads to a dramatic remission of pain. The present investigation was prompted by curiosity as to what the underlying algogenic mechanisms in these cases might be; and how a change in the vertical dimension should so modify them as to result in the disappearance of the pain symptoms. The study is necessarily of a speculative nature, and makes use of two representative cases, one of which was adjudged to have too little free-way, and the other too much. Principles of neuromuscular physiology are applied in attempting to explain the clinical phenomena involved, as well as to find a reason for certain electro-myographic artefacts noted in one of the cases, which would appear to call into question the notion that muscular hyperactivity, per se, is responsible for muscular pain. Potgieter, Monteith & Kemp (1983) have presented an hypothesis that the amount of free-way space present in an individual is an expression of the contractile power of the masseter and medial pterygoid muscles. They have also devised a method whereby, through cephalometric analysis, the optimal amount of free-way may be determined for an edentulous patient during denture construction. Furthermore, they have stated that their method has proved particularly effective in the treatment of denture-wearers presenting with symptoms of the myofascial pain dysfunction syndrome. However, in the light of this syndrome's multifactorial aetiology one must assume that only those symptoms which are related to a faulty free-way space are at issue. The purpose of the present investigation is to examine the latter assertion; and by the application of the suggested

  10. Increased proportion of megafibers in chronically painful muscles

    DEFF Research Database (Denmark)

    Andersen, Lars L; Suetta, Charlotte; Andersen, Jesper L

    2008-01-01

    . The percentage of megafibers was positively related to age and weekly working hours, indicating an effect of long-term exposure. In conclusion, this study shows that trapezius myalgia is associated with a significantly higher percentage of grossly hypertrophied type I muscle fibers with poor capillarization......Trapezius myalgia - chronic pain from the upper trapezius muscle - is frequent in female employees in monotonous stressful jobs, potentially due to chronic overload of type I muscle fibers. In this study, we investigated the intra-individual distribution of trapezius muscle fiber size......, and hypothesized that females with myalgia compared with matched healthy controls have a higher percentage of grossly hypertrophied type I fibers with poor capillarization. Forty-two female office workers with trapezius myalgia (MYA) and 20 healthy matched controls (CON) participated in the study. Standard...

  11. Effects of experimentally induced pain and fear of pain on trunk coordination and back muscle activity during walking.

    NARCIS (Netherlands)

    Lamoth, C.J.C.; Daffertshofer, A.; Meijer, O.G.; Moseley, G.; Wuisman, P.I.J.M.; Beek, P.J.

    2004-01-01

    OBJECTIVE: To examine the effects of experimentally induced pain and fear of pain on trunk coordination and erector spinae EMG activity during gait. DESIGN: In 12 healthy subjects, hypertonic saline (acute pain) and isotonic saline (fear of pain) were injected into erector spinae muscle, and unpredi

  12. Effects of experimentally induced pain and fear of pain on trunk coordination and back muscle activity during walking

    NARCIS (Netherlands)

    Lamoth, Claudine J.C.; Daffertshofer, Andreas; Meijer, Onno G.; Lorimer Moseley, G.; Wuisman, Paul I.J.M.; Beek, Peter J.

    2004-01-01

    Objective. To examine the effects of experimentally induced pain and fear of pain on trunk coordination and erector spinae EMG activity during gait. Design. In 12 healthy subjects, hypertonic saline (acute pain) and isotonic saline (fear of pain) were injected into erector spinae muscle, and unpredi

  13. Repeated Muscle Injury as a Presumptive Trigger for Chronic Masticatory Muscle Pain

    Directory of Open Access Journals (Sweden)

    Dean Dessem

    2011-01-01

    Full Text Available skeletal muscles sustain a significant loss of maximal contractile force after injury, but terminally damaged fibers can eventually be replaced by the growth of new muscle (regeneration, with full restoration of contractile force over time. After a second injury, limb muscles exhibit a smaller reduction in maximal force and reduced inflammation compared with that after the initial injury (i.e., repeated bout effect. In contrast, masticatory muscles exhibit diminished regeneration and persistent fibrosis, after a single injury; following a second injury, plasma extravasation is greater than after a single injury and maximal force is decreased more than after the initial injury. Thus, masticatory muscles do not exhibit a repeated bout effect and are instead increasingly damaged by repeated injury. We propose that the impaired ability of masticatory muscles to regenerate contributes to chronic muscle pain by leading to an accumulation of tissue damage, fibrosis, and a persistent elevation and prolonged membrane translocation of nociceptive channels such as P2X3 as well as enhanced expression of neuropeptides including CGRP within primary afferent neurons. These transformations prime primary afferent neurons for enhanced responsiveness upon subsequent injury thus triggering and/or exacerbating chronic muscle pain.

  14. Effects of experimental craniofacial pain on fine jaw motor control: a placebo-controlled double-blinded study.

    Science.gov (United States)

    Kumar, Abhishek; Castrillon, Eduardo; Svensson, Krister G; Baad-Hansen, Lene; Trulsson, Mats; Svensson, Peter

    2015-06-01

    The aim of the experiment was to test the hypothesis that experimental pain in the masseter muscle or temporomandibular joint (TMJ) would perturb the oral fine motor control, reflected in bigger variability of bite force values and jaw muscle activity, during repeated splitting of food morsels. Twenty healthy volunteers participated in four sessions. An intervention was made by injection of either 0.2 ml of monosodium glutamate/isotonic saline (MSG/IS) (randomized) in either the masseter or TMJ (randomized). The participants were asked to hold and split a flat-faced placebo tablet with their anterior teeth, thirty times each at baseline, during intervention and post-intervention. Pain was measured using a 0-10 visual analog scale. The force applied by the teeth to "hold" and "split" the tablet along with the corresponding electromyographic (EMG) activity of the jaw muscles and subject-based reports on perception of pain was recorded. The data analysis included a three-way analysis of variance model. The peak pain intensity was significantly higher during the painful MSG injections in the TMJ (6.1 ± 0.4) than the injections in masseter muscle (5.5 ± 0.5) (P = 0.037). Variability of hold force was significantly smaller during the MSG injection than IS injection in the masseter (P = 0.024). However, there was no significant effect of intervention on the variability of split force during the masseter injections (P = 0.769) and variability of hold and split force during the TMJ injections (P = 0.481, P = 0.545). The variability of the EMG activity of the jaw muscles did not show significant effects of intervention. Subject-based reports revealed that pain did not interfere in the ability to hold the tablet in 57.9 and 78.9 %, and the ability to split the tablet in 78.9 and 68.4 %, of the participants, respectively, during painful masseter and TMJ injections. Hence, experimental pain in the masseter muscle or TMJ did not have any robust effect in terms of bigger

  15. Neck muscle function in violinists/violists with and without neck pain.

    Science.gov (United States)

    Steinmetz, Anke; Claus, Andrew; Hodges, Paul W; Jull, Gwendolen A

    2016-04-01

    Neck pain is associated with changes in neuromuscular control of cervical muscles. Violin and viola playing requires good function of the flexor muscles to stabilize the instrument. This study investigated the flexor muscle behaviour in violin/viola players with and without neck pain using the craniocervical flexion test (CCFT). In total, 12 violin/viola players with neck pain, 21 violin/viola players without neck pain in the preceding 12 weeks and 21 pain-free non-musicians were included. Activity of the sternocleidomastoid muscles (SCM) was measured with surface electromyography (EMG) during the CCFT. Violin/viola players with neck pain displayed greater normalised SCM EMG amplitudes during CCFT than the pain-free musicians and non-musicians (P neck pain in violinists/violists is associated with altered behaviour of the superficial neck flexor muscles consistent with neck pain, despite the specific use of the deep and superficial neck flexors during violin playing.

  16. Is the long-latency stretch reflex in human masseter transcortical?

    Science.gov (United States)

    Pearce, Sophie L; Miles, Timothy S; Thompson, Philip D; Nordstrom, Michael A

    2003-06-01

    A long-latency stretch reflex (LLSR) has been described in the human masseter muscle, but its pathway remains uncertain. To investigate this, the excitability of corticomotoneuronal (CM) cells projecting to masseter motoneurons during the LLSR was assessed with transcranial magnetic stimulation (TMS). A facilitated response to TMS would be evidence of a LLSR pathway that traverses the motor cortex. Surface electromyogram electrodes were placed over the left or right masseter, and subjects ( n=10) bit on bars with their incisor teeth at 10% of maximal electromyographic activity (EMG). Servo-controlled displacements were imposed on the lower jaw to evoke a short- and long-latency stretch reflex in masseter. TMS intensity was just suprathreshold for a response in contralateral masseter. Trials consisted of: (1) stretch alone, (2) TMS alone, and (3) TMS with a preceding conditioning stretch at varied conditioning-testing (C-T) intervals chosen to combine TMS with the short-latency stretch reflex (3 ms, 5 ms) and the LLSR (23-41 ms). Masseter EMG was rectified and averaged. With TMS alone, mean (+/- SE) MEP area above baseline was 56+/-9%. The area of masseter MEPs above baseline in the C-T trials was calculated from each EMG average following subtraction of the response to stretch alone. Conditioning muscle stretch had no significant effect on masseter MEPs evoked by TMS with any C-T interval (ANOVA; P=0.90). In addition, subjects were unable to modify the SLSR or LLSR by voluntary command. It is concluded that the long-latency stretch reflex in the masseter does not involve the motor cortex and is not influenced by "motor set".

  17. Is myofascial pain in temporomandibular disorder patients a manifestation of delayed-onset muscle soreness?

    NARCIS (Netherlands)

    Koutris, M.; Lobbezoo, F.; Sümer, N.C.; Atis, E.S.; Türker, K.S.; Naeije, M.

    2013-01-01

    Objective: In a study to the possible role of overuse of the jaw muscles in the pathogenesis of jaw muscle pain, we used a protocol involving concentric and eccentric muscle contractions to provoke a state of delayed-onset muscle soreness (DOMS) in the jaw muscles of healthy individuals. We tested

  18. Is myofascial pain in temporomandibular disorder patients a manifestation of delayed-onset muscle soreness?

    NARCIS (Netherlands)

    Koutris, M.; Lobbezoo, F.; Sümer, N.C.; Atis, E.S.; Türker, K.S.; Naeije, M.

    2013-01-01

    Objective: In a study to the possible role of overuse of the jaw muscles in the pathogenesis of jaw muscle pain, we used a protocol involving concentric and eccentric muscle contractions to provoke a state of delayed-onset muscle soreness (DOMS) in the jaw muscles of healthy individuals. We tested w

  19. Anxiety and personality traits in patients with muscle related temporomandibular disorders.

    Science.gov (United States)

    Pallegama, R W; Ranasinghe, A W; Weerasinghe, V S; Sitheeque, M A M

    2005-10-01

    This study tested the hypothesis that muscle related temporomandibular disorder patients with cervical muscle pain exhibit greater degree of psychological distress compared with patients without cervical muscle pain and controls. Thirty-eight muscle related temporomandibular disorder patients including 10 patients with cervical muscle pain and 41 healthy individuals as controls participated in the study. State and trait anxiety levels were assessed with the Spielberger's state and trait anxiety inventory. Personality traits (extroversion, neuroticism, psychoticism and social desirability) were assessed using the Eysenck's personality questionnaire, and the pain intensities described over the muscles were recorded using a 100 mm visual analogue scale. The muscle related temporomandibular disorder patients, in general, exhibited significantly higher degrees of neuroticism and trait anxiety. The patients with cervical muscle pain demonstrated a significantly higher level of psychoticism compared with the patients without cervical muscle pain and the controls and a significantly higher state anxiety level than the controls. They also demonstrated higher pain intensities in masseter and temporalis muscles compared with patients without cervical muscle pain. It has been suggested that either subjects with psychological distress are prone to temporomandibular disorders, or psychological distress is a manifestation of existing chronic pain conditions. The present findings demand further investigations and broader approach in management, as muscle related temporomandibular disorder patients with cervical muscle pain were both physically and psychologically compromised to a greater degree compared with patients without cervical muscle pain.

  20. Peripheral mGluR5 antagonist attenuated craniofacial muscle pain and inflammation but not mGluR1 antagonist in lightly anesthetized rats.

    Science.gov (United States)

    Lee, Ho Jeong; Choi, Hyo Soon; Ju, Jin Sook; Bae, Yong Chul; Kim, Sung Kyo; Yoon, Young Wook; Ahn, Dong Kuk

    2006-10-16

    The present study investigated the role of peripheral group I metabotropic glutamate receptors (mGluRs) in MO-induced nociceptive behaviour and inflammation in the masseter muscles of lightly anesthetized rats. Experiments were carried out on male Sprague-Dawley rats weighing 300-400 g. After initial anesthesia with sodium pentobarbital (40 mg/kg, i.p.), one femoral vein was cannulated and connected to an infusion pump for intravenous infusion of sodium pentobarbital. The rate of infusion was adjusted to provide a constant level of anesthesia. Mustard oil (MO, 30 microl) was injected into the mid-region of the left masseter muscle via a 30-gauge needle over 10s. After 30 microl injection of 5, 10, 15, or 20% MO into the masseter muscle, the total number of hindpaw shaking behaviour and extravasated Evans' blue dye concentration in the masseter muscle were significantly higher in the MO-treated group in a dose-dependent manner compared with the vehicle (mineral oil)-treated group. Intramuscular pretreatment with 3 or 5% lidocaine reduced MO-induced hindpaw shaking behaviour and increases in extravasated Evans' blue dye concentration. Intramuscular pretreatment with 5 mM MCPG, non-selective group I/II mGluR antagonist, or MPEP, a selective group I mGluR5 antagonist, produced a significant attenuation of MO-induced hindpaw shaking behaviour and increases in extravasated Evans' blue dye concentration in the masseter muscle while LY367385, a selective group I mGluR1 antagonist, did not affect MO-induced nociceptive behaviour and inflammation in the masseter muscle. These results indicate that peripheral mGluR5 plays important role in mediating MO-induced nociceptive behaviour and inflammation in the craniofacial muscle.

  1. Experimental muscle pain decreases the frequency threshold of electrically elicited muscle cramps.

    Science.gov (United States)

    Serrao, Mariano; Arendt-Nielsen, Lars; Ge, Hong-You; Pierelli, Francesco; Sandrini, Giorgio; Farina, Dario

    2007-09-01

    This study in humans tested the hypothesis that nociceptive muscle afferent input facilitates the occurrence of muscle cramps. In 13 healthy adults, muscle cramps were experimentally induced in the foot by stimulating the tibialis posterior nerve at the ankle with 2-s bursts of stimuli separated by 30 s, with stimulation frequency increasing by 2-Hz increments from 10 Hz until the cramp appeared. The minimum stimulation frequency that induced the cramp was defined "cramp frequency threshold". In 2 days, elicitation of the cramp was performed in the two-feet with and without (baseline condition) injection of hypertonic (painful condition) or isotonic (control condition) saline into the deep midportion of the flexor hallucis brevis muscle, from where surface EMG signals were recorded. The cramp frequency threshold was lower for the painful condition with respect to its baseline (mean +/- SE, hypertonic saline: 25.7 +/- 2.1 Hz, corresponding baseline: 31.2 +/- 2.8 Hz; P cramp than immediately before the stimulation that elicited the cramp (pre-cramp: 13.9 +/- 1.6 muV and 75.4 +/- 3.8 Hz, respectively; post-cramp: 19.9 +/- 3.2 muV and 101.6 +/- 6.0 Hz; P muscle afferent activity induced by injection of hypertonic saline facilitates the generation of electrically elicited muscle cramps.

  2. Relation Between Muscle Activation Pattern and Pain : An Explorative Study in a Bassists Population

    NARCIS (Netherlands)

    Woldendorp, Kees H.; van de Werk, Pieter; Boonstra, Anne M.; Stewart, Roy E.; Otten, Egbert

    2013-01-01

    Objective: To explore the muscle activation patterns in relation to pain complaints in bassists studied during a musical task. This study was based on the assumption that pain complaints are caused by increased muscle activation during playing or relaxation and/or faster onset of fatigue of muscles.

  3. Relation Between Muscle Activation Pattern and Pain : An Explorative Study in a Bassists Population

    NARCIS (Netherlands)

    Woldendorp, Kees H.; van de Werk, Pieter; Boonstra, Anne M.; Stewart, Roy E.; Otten, Egbert

    Objective: To explore the muscle activation patterns in relation to pain complaints in bassists studied during a musical task. This study was based on the assumption that pain complaints are caused by increased muscle activation during playing or relaxation and/or faster onset of fatigue of muscles.

  4. Changes in intramuscular cytokine levels during masseter inflammation in male and female rats

    OpenAIRE

    Niu, Katelyn Y.; Ro, Jin Y.

    2010-01-01

    The present study was conducted to examine cytokine profiles in the masseter muscle before and after complete Freund’s adjuvant (CFA)-induced inflammation and possible sex differences in the cytokine levels. Age matched male and female Sprague Dawley rats were injected with CFA in the mid-region of the masseter muscle. Muscle tissue surrounding the injection site was extracted 6 hrs, 1, 3 and 7 days after the injection to measure TNF-α, IL-1β, IL-6 and IL-4 levels with Luminex multi-analyte p...

  5. Effect of intramuscular injection of botulinum toxin type A and triamcinolone to the masseter muscle on the development of mandible: an experimental study%咬肌内注射A型肉毒毒素和曲安奈德对大鼠下颌骨发育影响的实验研究

    Institute of Scientific and Technical Information of China (English)

    黄进军; 王晋煌; 柳大烈; 陈伯华; 陈兵

    2011-01-01

    Objective To evaluate the effect of intramuscular injection of botulinum toxin type A and triamcinolone to the masseter muscle on the development of mandible. Methods Thirty 28-days-old Wistar rats were divided into four groups: botulinum toxin type A group ( B group, 8 rats) , triamcinolone group (T group,8 rats) , botulinum toxin type A and triamcinolone group ( BT group, 8 rats) . control group ( C group, 6 rats) .The right side of masseter muscle was injected with the drugs corresponding to its group and the left side of masseter muscle was injected with saline. The control group was only anaesthetised. CT scan and 3D reconstruction were taken when the rats were 75 days old. Seven cephalometric points were digitized and selected 7 linear distances were measured. The rats were killed with an overdose of 10% chloral hydrate after CT scan. Masseter muscles of each side were obtained and weighted immediately. Results Significant atrophy of masseter muscles were observed in the B group and BT group. Mandibular length Ⅲ ( Go-Iia) . mandibular height Ⅱ ( Cor-GoT)on the right side was less than that on the left side in B group. Mandibular height Ⅱ on the right side was less than that on the left side in BT group. The variances of mandibular height Ⅱ and mandibular height Ⅲ ( ConGoT) on the right side between 4 groups were significant. Conclusion Changes on mandibular height after intramuscular injection of botulinum toxin type A to the masseter muscle were seen. But alterations of mandibular length and bigonial width were not found. Cephalometric changes were not obvious on the triamcinolone group.%目的 探讨咬肌内注射A型肉毒毒素和曲安奈德对大鼠下颌骨发育的影响.方法 取28日龄雄性Wistar大鼠为实验对象,随机分为4组:A型肉毒毒素组(B组,n=8)、曲安奈德组(T组,n=8)、A型肉毒毒素+曲安奈德组(BT组,n=8)、对照组(C组,n=6),每组大鼠取右侧咬肌并向肌内注射相应的药物,左侧注射等

  6. Temporal summation in muscles and referred pain areas: an experimental human study.

    Science.gov (United States)

    Arendt-Nielsen, L; Graven-Nielsen, T; Svensson, P; Jensen, T S

    1997-10-01

    The aim of the present study was to assess temporal summation within saline-induced, localized and referred muscle pain areas. The sensibility to single and repeated electrical stimuli were assessed in the muscle by means of needle electrodes and in the referred pain area by surface stimulation. The study demonstrates that temporal summation of nociceptive input from muscles exists and that the responses to single and repeated nociceptive stimuli of the referred pain area are facilitated.

  7. Effects of strength and endurance training of superficial and deep neck muscles on muscle activities and pain levels of females with chronic neck pain.

    Science.gov (United States)

    Borisut, Sudarat; Vongsirinavarat, Mantana; Vachalathiti, Roongtiwa; Sakulsriprasert, Prasert

    2013-09-01

    [Purpose] To compare muscle activities and pain levels of females with chronic neck pain receiving different exercise programs. [Subjects and Methods] One hundred females with chronic neck pain participated in this study. They were randomly allocated into 4 groups (n = 25) on the basis of the exercises performed as follows: strength-endurance exercise, craniocervical flexion exercise, combination of strength-endurance and craniocervical flexion exercise and control groups. Pain, disability levels and changes in the muscle activities of the cervical erector spinae (CE), sternocleidomastoid (SCM), anterior scalenes (AS) and upper trapezius (UT) muscles were evaluated before and after the interventions. [Results] After 12 weeks of exercise intervention, all three exercise groups showed improvements in pain and disability. The muscle activities during the typing task were significantly different from the control group in all three exercise groups for all muscles except those of the extensor muscles in the craniocervical flexion exercise group. [Conclusion] The results of this study indicate that exercises for the cervical muscles improve pain and disability. The exercise programs reduced the activities of almost all cervical muscles.

  8. Single cell morphology of muscle in patients with chronic muscle pain

    DEFF Research Database (Denmark)

    Jacobsen, Søren; Bartels, E M; Danneskiold-Samsøe, B

    1991-01-01

    In 119 patients referred with suspected fibromyalgia, biopsies from the quadriceps muscle were analyzed for "rubber band" morphology, and isokinetic quadriceps strength was measured. Eighty-four fulfilled the criteria for fibromyalgia, 26 had chronic myofascial pain (CMP) and 9 had other diseases...... to the biopsy score. "Rubber band" morphology is seen more often in fibromyalgia patients than in CMP patients. The exact genesis of this phenomenon is still unknown but theories connected with the possible pathogenesis of the syndrome are presented....

  9. No release of interstitial glutamate in experimental human model of muscle pain

    DEFF Research Database (Denmark)

    Ashina, M.; Jørgensen, M.; Stallknecht, Bente;

    2005-01-01

    Glutamate may be released from muscle nociceptors and thereby contribute to mechanisms underlying acute and chronic muscle pain. In vivo concentration of glutamate during muscle pain has not previously been studied in either animals or humans. In the present study, we aimed to study the in vivo...... flow increased significantly over time in response to infusion of chemical mixture and placebo (p = 0.001). However, we found no difference in changes in muscle blood flow between chemical mixture and placebo (p > 0.05). In conclusion, the present study demonstrates no signs of increased release...... of glutamate from myofascial nociceptors during and after acute experimentally induced muscle pain and tenderness....

  10. The influence of induced shoulder muscle pain on rotator cuff and scapulothoracic muscle activity during elevation of the arm.

    Science.gov (United States)

    Castelein, Birgit; Cools, Ann; Parlevliet, Thierry; Cagnie, Barbara

    2017-03-01

    Altered recruitment of rotator cuff and scapulothoracic muscles has been identified in patients with subacromial impingement syndrome. To date, however, the cause-consequence relationship between pain and altered muscle recruitment has not been fully unraveled. The effect of experimental shoulder pain induced by injection of hypertonic saline in the supraspinatus on the activity of the supraspinatus, infraspinatus, subscapularis, trapezius, and serratus anterior activity was investigated during the performance of an elevation task by use of muscle functional magnetic resonance imaging in 25 healthy individuals. Measurements were taken at 4 levels (C6-C7, T2-T3, T3-T4, and T6-T7) at rest and after the elevation task performed without and with experimental shoulder pain. During arm elevation, experimentally induced pain caused a significant activity reduction, expressed as reduction in T2 shift of the IS (P = .029). No significant changes in T2 shift values were found for the other rotator cuff muscles or the scapulothoracic muscles. This study demonstrates that acute experimental shoulder pain has an inhibitory effect on the activity of the IS during arm elevation. Acute experimental shoulder pain did not seem to influence the scapulothoracic muscle activity significantly. The findings suggest that rotator cuff muscle function (infraspinatus) should be a consideration in the early management of patients with shoulder pain. Copyright © 2017 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

  11. Role of temporomandibular disorders (TMD) in facial pain: occlusion, muscle and TMJ pain.

    Science.gov (United States)

    Rauhala, K; Oikarinen, K S; Raustia, A M

    1999-10-01

    Temporomandibular disorders (TMD) which comprise myogenic and arthralgic components have been reported to predispose subjects to headache and facial pain. The aim of this study was to evaluate the role of these components in patients with facial pain and to investigate the influence of treatment of TMD on pain of these patients. The subject group consisted of 25 patients suffering from facial pain. The clinical stomatognathic examination was performed before conservative treatment of TMD, and one-two weeks, three months and one year after treatment. The severity of TMD was assessed using the anamnestic (AI) and clinical dysfunction (DI) indices of Helkimo. The intensity of pain was evaluated on a numerical rating scale (NRS). According to clinical findings the patients were classified to following diagnostic subgroups: TMD myo (mainly myogenic), TMD arthro (mainly arthrogenous) and TMD comb (both myogenic and arthrogenous components involved). Fifteen patients were classified in the TMD myo group, nine in the TMD comb group and one in the TMD arthro group. The DI index decreased significantly one-two weeks after treatment and remained at this level at three month and one year follow-up examinations. At the first examination the TMD myo group had the highest level of NRS index, which decreased significantly during the time of follow-up, while no significant changes were found in other groups. Bruxism reported by the patient had a positive correlation with the amount of painful muscles on the right side at first examination. The results show that facial pain combined with TMD may be mostly of myogenic origin, and myogenic pain seems to have most favorable response to conservative treatment of TMD.

  12. Effects of experimental muscle pain on shoulder-abduction force steadiness and muscle activity in healthy subjects

    DEFF Research Database (Denmark)

    Bandholm, Thomas Quaade; Rasmussen, Lars; Aagaard, Per;

    2007-01-01

    We previously demonstrated that the steadiness of shoulder abduction is reduced in patients with subacromial impingement syndrome (SIS), which might be related to shoulder pain associated with the SIS. The aim of the present study was to examine the acute effects of experimental shoulder muscle p...... explanation may be that, even though the adopted experimental pain-paradigm may reflect the SIS in terms of the painful structures, it might not reflect the adaptations in the central nervous system seen with chronic pain....

  13. Women with dysmenorrhea are hypersensitive to experimental deep muscle pain across the menstrual cycle.

    Science.gov (United States)

    Iacovides, Stella; Baker, Fiona C; Avidon, Ingrid; Bentley, Alison

    2013-10-01

    Primary dysmenorrhea is a common painful condition in women that recurs every month across the reproductive years. The recurrent nociceptive input into the central nervous system that occurs during menstruation each month in women with dysmenorrhea is hypothesized to lead to increased sensitivity to painful stimuli. We investigated whether women with primary dysmenorrhea are hyperalgesic to deep muscle pain induced by a cleanly nociceptive method of hypertonic saline injection. Pain stimulation was applied both within an area of referred menstrual pain (lower back) and at a remote site outside of referred menstrual pain (forearm) in 12 healthy women with severe dysmenorrhea and 9 healthy women without dysmenorrhea, at 3 phases of the menstrual cycle: menstruation and follicular and luteal phases. Women rated their pain severity on a 100-mm visual analog scale every 30 seconds after injection until the pain subsided. In both groups of women, menstrual cycle phase had no effect on the reported intensity and duration of muscle pain. However, women with dysmenorrhea had increased sensitivity to experimental muscle pain both at the site of referred pain and at a remote nonpainful site, as assessed by peak pain severity visual analog scale rating, area under the visual analog scale curve, and pain duration, compared to women without dysmenorrhea. These data show that women with severe primary dysmenorrhea, who experience monthly menstrual pain, are hyperalgesic to deep muscle pain compared to women without dysmenorrhea. Our findings that dysmenorrheic women are hyperalgesic to a clinically relevant, deep muscle pain in areas within and outside of referred menstrual pain indicates lasting changes in pain sensitivity outside of the painful period during menstruation. Copyright © 2013 American Pain Society. Published by Elsevier Inc. All rights reserved.

  14. Effectiveness of botulinum toxin type A treatment of neck pain related to nocturnal bruxism: a case report

    Science.gov (United States)

    Santamato, Andrea; Panza, Francesco; Di Venere, Daniela; Solfrizzi, Vincenzo; Frisardi, Vincenza; Ranieri, Maurizio; Fiore, Pietro

    2010-01-01

    Objective This case report describes a patient with nocturnal bruxism and related neck pain treated with botulinum toxin type A (BTX-A). Clinical Features The patient was a 27-year-old man with nocturnal bruxism and difficulty in active mouth opening and chewing and neck pain at rest. His numeric pain score was 7 of 10. Surface electromyography of the temporalis and masseter muscles showed typical signs of hyperactivity, characterized by compound muscle action potential amplitude alterations. Intervention and Outcome After clinical evaluation, he was treated with BTX-A to reduce masseter and temporalis muscle hyperactivity. After 3 days of treatment with BTX-A, with each masseter muscle injected with a dose of about 40 mouse units with a dilution of 1 mL and with temporal muscle bilaterally injected with 25 mouse units with the same dilution, a decrease in bruxism symptoms was reported. Neck pain also decreased after the first treatment (visual analog scale of 2/10) and then resolved completely. After 4 weeks, electromyography showed the reduction of muscle hyperactivity with a decrease in the amplitude of the motor action potential. The same reduction in signs and symptoms was still present at assessment 3 months posttreatment. Conclusion These findings suggest that BTX-A may be a therapeutic option for the treatment of bruxism and related disorders. PMID:22027036

  15. Genetic reduction of chronic muscle pain in mice lacking calcium/calmodulin-stimulated adenylyl cyclases

    Directory of Open Access Journals (Sweden)

    Petrovic Michele J

    2006-02-01

    Full Text Available Abstract Background The Ca2+/calmodulin-stimulated adenylyl cyclase (AC isoforms AC1 and AC8, couple NMDA receptor activation to cAMP signaling pathways in neurons and are important for development, learning and memory, drug addiction and persistent pain. AC1 and AC8 in the anterior cingulate cortex (ACC and the spinal cord were previously shown to be important in subcutaneous inflammatory pain. Muscle pain is different from cutaneous pain in its characteristics as well as conducting fibers. Therefore, we conducted the present work to test the role of AC1 and AC8 in both acute persistent and chronic muscle pain. Results Using an acute persistent inflammatory muscle pain model, we found that the behavioral nociceptive responses of both the late phase of acute muscle pain and the chronic muscle inflammatory pain were significantly reduced in AC1 knockout (KO and AC1&8 double knockout (DKO mice. Activation of other adenylyl cyclases in these KO mice by microinjection of forskolin into the ACC or spinal cord, but not into the peripheral tissue, rescued the behavioral nociceptive responses. Additionally, intra-peritoneal injection of an AC1 inhibitor significantly reduced behavioral responses in both acute persistent and chronic muscle pain. Conclusion The results of the present study demonstrate that neuronal Ca2+/calmodulin-stimulated adenylyl cyclases in the ACC and spinal cord are important for both late acute persistent and chronic inflammatory muscle pain.

  16. Site-specific muscle hyper-reactivity in musicians with occupational upper limb pain.

    Science.gov (United States)

    Moulton, B; Spence, S H

    1992-07-01

    Fourteen musicians who reported a history of pain in the upper limb associated with the playing of their instruments were compared with a sample of pain-free musicians, matched for age, sex and musical instrument. Four tasks were presented in random order and included neutral, general stressor, personal stressor and pain stressor tasks. Ratings of stressfulness and recordings of skin conductance level confirmed the effectiveness of the experimental manipulations for both subject groups. No differences were found between groups or tasks for frontalis surface electromyograph (EMG) activity. Evidence was found, however, of EMG elevation in flexor and trapezius muscles on the pain side for the pain subjects, in response to the task involving recall of a pain experience. This elevation was not found for the pain-free controls or for other stressor tasks, although some elevation in response to the pain stressor task was found for pain subjects in the trapezius muscles of the non-pain side. The duration of return to baseline of EMG following the pain stressor task was found to be extended in pain subjects for the trapezius, but not for the flexor muscles of the pain side. The findings suggest that site-specific muscle hyper-reactivity may play a role in the development and maintenance of occupational upper limb pain in musicians.

  17. Prevalence and anatomical location of muscle tenderness in adults with nonspecific neck/shoulder pain

    DEFF Research Database (Denmark)

    Andersen, Lars L; Hansen, Klaus; Mortensen, Ole S

    2011-01-01

    Many adults experience bothersome neck/shoulder pain. While research and treatment strategies often focus on the upper trapezius, other neck/shoulder muscles may be affected as well. The aim of the present study is to evaluate the prevalence and anatomical location of muscle tenderness in adults...... with nonspecific neck/shoulder pain....

  18. Body position effects on sternocleidomastoid and masseter EMG pattern activity in patients undergoing occlusal splint therapy.

    Science.gov (United States)

    Ormeño, G; Miralles, R; Santander, H; Casassus, R; Ferrer, P; Palazzi, C; Moya, H

    1997-10-01

    This study was conducted in order to determine the effects of body position on electromyographic (EMG) activity of sternocleidomastoid and masseter muscles, in 15 patients with myogenic cranio-cervical-mandibular dysfunction undergoing occlusal splint therapy. EMG activity was recorded by placing surface electrodes on the sternocleidomastoid and masseter muscles (contralateral to the habitual sleeping side of each patient). EMG activity at rest and during swallowing of saliva and maximal voluntary clenching was recorded in the following body positions: standing, supine and lateral decubitus. In the sternocleidomastoid muscle significant higher EMG activities at rest and during swallowing were recorded in the lateral decubitus position, whereas during maximal voluntary clenching EMG activity did not change. In the masseter muscle significant higher EMG activity during maximal voluntary clenching in a standing position was observed, whereas EMG activity at rest and during swallowing did not change. The opposite pattern of EMG activity supports the idea that there may exist a differential modulation of the motor neuron pools of the sternocleidomastoid and masseter muscles, of peripheral and/or central origin. This suggests that the presence of parafunctional habits and body position could be closely correlated with the clinical symptomatology in these muscles in patients with myogenic craniomandibular dysfunction.

  19. Effectiveness of hip muscle strengthening in patellofemoral pain syndrome patients: a systematic review

    Science.gov (United States)

    Santos, Thiago R. T.; Oliveira, Bárbara A.; Ocarino, Juliana M.; Holt, Kenneth G.; Fonseca, Sérgio T.

    2015-01-01

    Introduction: Patellofemoral pain syndrome (PFPS) is characterized by anterior knee pain, which may limit the performance of functional activities. The influence of hip joint motion on the development of this syndrome has already been documented in the literature. In this regard, studies have investigated the effectiveness of hip muscle strengthening in patients with PFPS. Objectives: The aims of this systematic review were (1) to summarize the literature related to the effects of hip muscle strengthening on pain intensity, muscle strength, and function in individuals with PFPS and (2) to evaluate the methodological quality of the selected studies. Method: A search for randomized controlled clinical trials was conducted using the following databases: Google Scholar, MEDLINE, PEDro, LILACS, and SciELO. The selected studies had to distinguish the effects of hip muscle strengthening in a group of patients with PFPS, as compared to non-intervention or other kinds of intervention, and had to investigate the following outcomes: pain, muscle strength, and function. The methodological quality of the selected studies was analyzed by means of the PEDro scale. Results: Seven studies were selected. These studies demonstrated that hip muscle strengthening was effective in reducing pain. However, the studies disagreed regarding the treatments' ability to improve muscle strength. Improvement in functional capabilities after hip muscle strengthening was found in five studies. Conclusion: Hip muscle strengthening is effective in reducing the intensity of pain and improving functional capabilities in patients with PFPS, despite the lack of evidence for its ability to increase muscle strength. PMID:26039034

  20. Effectiveness of hip muscle strengthening in patellofemoral pain syndrome patients: a systematic review

    Directory of Open Access Journals (Sweden)

    Thiago R. T. Santos

    2015-06-01

    Full Text Available Introduction: Patellofemoral pain syndrome (PFPS is characterized by anterior knee pain, which may limit the performance of functional activities. The influence of hip joint motion on the development of this syndrome has already been documented in the literature. In this regard, studies have investigated the effectiveness of hip muscle strengthening in patients with PFPS. Objectives: The aims of this systematic review were (1 to summarize the literature related to the effects of hip muscle strengthening on pain intensity, muscle strength, and function in individuals with PFPS and (2 to evaluate the methodological quality of the selected studies. Method: A search for randomized controlled clinical trials was conducted using the following databases: Google Scholar, MEDLINE, PEDro, LILACS, and SciELO. The selected studies had to distinguish the effects of hip muscle strengthening in a group of patients with PFPS, as compared to non-intervention or other kinds of intervention, and had to investigate the following outcomes: pain, muscle strength, and function. The methodological quality of the selected studies was analyzed by means of the PEDro scale. Results: Seven studies were selected. These studies demonstrated that hip muscle strengthening was effective in reducing pain. However, the studies disagreed regarding the treatments' ability to improve muscle strength. Improvement in functional capabilities after hip muscle strengthening was found in five studies. Conclusion: Hip muscle strengthening is effective in reducing the intensity of pain and improving functional capabilities in patients with PFPS, despite the lack of evidence for its ability to increase muscle strength.

  1. Effect of two contrasting types of physical exercise on chronic neck muscle pain

    DEFF Research Database (Denmark)

    Andersen, L.L.; Kjær, Michael; Søgaard, Kirsten

    2008-01-01

    Objective. The prevalence of neck muscle pain has steadily increased and especially pain from the descending part of the trapezius muscle has been associated with monotonous work tasks such as computer work. Physical exercise is generally recommended as treatment, but it is unclear which type...... for the affected muscle, general fitness training performed as leg bicycling with relaxed shoulders, or a reference intervention without physical activity. The main outcome measure was an acute and prolonged change in intensity of neck muscle pain (100-mm visual analog scale [VAS]). Results. A decrease of 35 mm...

  2. Effect of two contrasting types of physical exercise on chronic neck muscle pain

    DEFF Research Database (Denmark)

    Andersen, Lars L; Kjaer, Michael; Søgaard, Karen

    2008-01-01

    OBJECTIVE: The prevalence of neck muscle pain has steadily increased and especially pain from the descending part of the trapezius muscle has been associated with monotonous work tasks such as computer work. Physical exercise is generally recommended as treatment, but it is unclear which type...... for the affected muscle, general fitness training performed as leg bicycling with relaxed shoulders, or a reference intervention without physical activity. The main outcome measure was an acute and prolonged change in intensity of neck muscle pain (100-mm visual analog scale [VAS]). RESULTS: A decrease of 35 mm...

  3. Effectiveness of core muscle strengthening for improving pain and dynamic balance among female patients with patellofemoral pain syndrome.

    Science.gov (United States)

    Chevidikunnan, Mohamed Faisal; Al Saif, Amer; Gaowgzeh, Riziq Allah; Mamdouh, Khaled A

    2016-05-01

    [Purpose] Patellofemoral pain syndrome is a frequent musculoskeletal disorder, which can result from core muscles instability that can lead to pain and altered dynamic balance. The objective of this study is to assess the effect of core muscle strengthening on pain and dynamic balance in female patients with patellofemoral pain syndrome. [Subjects and Methods] Twenty female patients with age ranging from 16 to 40 years with patellofemoral pain syndrome were divided into study (N=10) and control (N=10) groups. Both groups were given 4 weeks of conventional physical therapy program and an additional core muscle strengthening for the study group. The tools used to assess the outcome were Visual Analogue Scale and Star Excursion Balance Test. [Results] The results of the study show that participants in the study group revealed a significantly greater improvement in the intensity of pain and dynamic balance as compared to the control group. [Conclusion] Adding a core muscle-strengthening program to the conventional physical therapy management improves pain and dynamic balance in female patients with patellofemoral pain syndrome.

  4. Association of neck pain, disability and neck pain during maximal effort with neck muscle strength and range of movement in women with chronic non-specific neck pain.

    Science.gov (United States)

    Ylinen, Jari; Takala, Esa-Pekka; Kautiainen, Hannu; Nykänen, Matti; Häkkinen, Arja; Pohjolainen, Timo; Karppi, Sirkka-Liisa; Airaksinen, Olavi

    2004-10-01

    Several studies have reported lower neck muscle strength in patients with chronic neck pain compared to healthy controls. The aim of the present study was to evaluate the association between the severity of neck pain and disability with neck strength and range of movement in women suffering from chronic neck pain. One hundred and seventy-nine female office workers with chronic neck pain were selected to the study. The outcome was assessed by the self-rating questionnaires on neck pain (visual analogue scale, Vernon's disability index, Neck pain and disability index) and by measures of the passive range of movement (ROM) and maximal isometric neck muscle strength. No statistically significant correlation was found between perceived neck pain and the disability indices and the maximal isometric neck strength and ROM measures. However, the pain values reported during the strength tests were inversely correlated with the results of strength tests (r=-0.24 to -0.46), showing that pain was associated with decreased force production. About two-thirds of the patients felt pain during test efforts. Pain may prevent full effort during strength tests and hence the production of maximal force. Thus in patients with chronic neck pain the results do not always describe true maximal strength, but rather the patients' ability to bear strain, which may be considerably influenced by their painful condition. The results of the present study suggest that rehabilitation in cases of chronic neck pain should aim at raising tolerance to mechanical strain.

  5. Effect of physical training on pain sensitivity and trapezius muscle morphology

    DEFF Research Database (Denmark)

    Nielsen, Pernille Kofoed; Andersen, Lars L; Olsen, Henrik B

    2010-01-01

    strength training (SST); (2) general fitness training (GFT); or (3) reference intervention (REF). Differences in muscle morphology could not be detected by ultrasound imaging. Significantly lower pressure pain threshold (PPT) and shoulder torque were observed for MYA, indicating pain-related lack of full...... activation. After 10 weeks, increased shoulder torque and PPT of the painful trapezius were observed in SST solely. The PPT of a pain-free reference muscle was increased in response to both SST and GFT, indicating a general effect of physical activity on pain perception. This study shows clinically relevant...

  6. Analysis of scapular muscle EMG activity in patients with idiopathic neck pain: a systematic review.

    Science.gov (United States)

    Castelein, Birgit; Cools, Ann; Bostyn, Emma; Delemarre, Jolien; Lemahieu, Trees; Cagnie, Barbara

    2015-04-01

    It is proposed that altered scapular muscle function can contribute to abnormal loading of the cervical spine. However, it is not clear if patients with idiopathic neck pain show altered activity of the scapular muscles. The aim of this paper was to systematically review the literature regarding the differences or similarities in scapular muscle activity, measured by electromyography ( = EMG), between patients with chronic idiopathic neck pain compared to pain-free controls. Case-control (neck pain/healthy) studies investigating scapular muscle EMG activity (amplitude, timing and fatigue parameters) were searched in Pubmed and Web of Science. 25 articles were included in the systematic review. During rest and activities below shoulder height, no clear differences in mean Upper Trapezius ( = UT) EMG activity exist between patients with idiopathic neck pain and a healthy control group. During overhead activities, no conclusion for scapular EMG amplitude can be drawn as a large variation of results were reported. Adaptation strategies during overhead tasks are not the same between studies. Only one study investigated timing of the scapular muscles and found a delayed onset and shorter duration of the SA during elevation in patients with idiopathic neck pain. For scapular muscle fatigue, no definite conclusions can be made as a wide variation and conflicting results are reported. Further high quality EMG research on scapular muscles (broader than the UT) is necessary to understand/draw conclusions on how scapular muscles react in the presence of idiopathic neck pain.

  7. Effect of contrasting physical exercise interventions on rapid force capacity of chronically painful muscles

    DEFF Research Database (Denmark)

    Andersen, Lars L; Andersen, Jesper L; Suetta, Charlotte

    2009-01-01

    torque increased 18-29% (P muscle fibers hypertrophied 20% (P muscles is highly responsive......Rapid force capacity of chronically painful muscles is inhibited markedly more than maximal force capacity and is therefore relevant to assess in rehabilitation settings. Our objective was to investigate the effect of two contrasting types of physical exercise on rapid force capacity, as well...... as neural and muscular adaptations in women with chronic neck muscle pain. A group of employed women (n = 42) with a clinical diagnosis of trapezius myalgia participated in a 10-wk randomized controlled trial; specific strength training of the neck/shoulder muscles, general fitness training performed as leg...

  8. The effect of experimental low back pain on lumbar muscle activity in people with a history of clinical low back pain: a muscle functional MRI study.

    Science.gov (United States)

    Danneels, Lieven; Cagnie, Barbara; D'hooge, Roseline; De Deene, Yves; Crombez, Geert; Vanderstraeten, Guy; Parlevliet, Thierry; Van Oosterwijck, Jessica

    2016-02-01

    In people with a history of low back pain (LBP), structural and functional alterations have been observed at several peripheral and central levels of the sensorimotor pathway. These existing alterations might interact with the way the sensorimotor system responds to pain. We examined this assumption by evaluating the lumbar motor responses to experimental nociceptive input of 15 participants during remission of unilateral recurrent LBP. Quantitative T2 images (muscle functional MRI) were taken bilaterally of multifidus, erector spinae, and psoas at several segmental levels (L3 upper and L4 upper and lower endplate) and during several conditions: 1) at rest, 2) upon trunk-extension exercise without pain, and 3) upon trunk-extension exercise with experimental induced pain at the clinical pain-side (1.5-ml intramuscular hypertonic saline injections in erector spinae). Following experimental pain induction, muscle activity levels similarly reduced for all three muscles, on both painful and nonpainful sides, and at multiple segmental levels (P = 0.038). Pain intensity and localization from experimental LBP were similar as during recalled clinical LBP episodes. In conclusion, unilateral and unisegmental experimental LBP exerts a generalized and widespread decrease in lumbar muscle activity during remission of recurrent LBP. This muscle response is consistent with previous observed patterns in healthy people subjected to the same experimental pain paradigm. It is striking that similar inhibitory patterns in response to pain could be observed, despite the presence of preexisting alterations in the lumbar musculature during remission of recurrent LBP. These results suggest that motor output can modify along the course of recurrent LBP.

  9. Clenching and grinding: effect on masseter and sternocleidomastoid electromyographic activity in healthy subjects.

    Science.gov (United States)

    Venegas, Macarena; Valdivia, José; Fresno, María Javiera; Miralles, Rodolfo; Gutiérrez, Mario Felipe; Valenzuela, Saúl; Fuentes, Aler

    2009-07-01

    This study compares the effect of clenching and grinding on masseter and sternocleidomastoid electromyographic (EMG) activity during different jaw posture tasks in the sagittal plane. The study included 34 healthy subjects with natural dentition, Class I bilateral molar Angle relationship, and absence of posterior occlusal contacts during mandibular protrusion. An inclusion criterion was that subjects had to be free of signs and symptoms of any dysfunction of the masticatory system. Bipolar surface electrodes were located on the right masseter and sternocleidomastoid muscles. EMG activity was recorded while the subjects were in standing position, during the following jaw posture tasks: A. maximal clenching in the intercuspal position; B. grinding from intercuspal position to edge-to-edge protrusive contact position; C. maximal clenching in the edge-to-edge protrusive contact position; D. grinding from edge-to-edge protrusive contact position to intercuspal position; E. grinding from retrusive contact position to intercuspal position. EMG activities in tasks B, C, D, and E were significantly lower than in task A in both muscles (mixed model with unstructured covariance matrix). EMG activity among tasks B, C, D, and E did not show significant differences in both muscles, except between tasks D and E in the masseter muscle. A higher effect was observed on the masseter than on the sternocleidomastoid muscle to avoid excessive muscular activity during clenching and grinding. The EMG patterns observed could be of clinical importance in the presence of parafunctional habits, i.e., clenching and/or grinding.

  10. Changed activation, oxygenation, and pain response of chronically painful muscles to repetitive work after training interventions: a randomized controlled trial

    DEFF Research Database (Denmark)

    Søgaard, Karen; Blangsted, Anne Katrine; Nielsen, Pernille Kofoed;

    2012-01-01

    The aim of this randomized controlled trial was to assess changes in myalgic trapezius activation, muscle oxygenation, and pain intensity during repetitive and stressful work tasks in response to 10 weeks of training. In total, 39 women with a clinical diagnosis of trapezius myalgia were randomly...... assigned to: (1) general fitness training performed as leg-bicycling (GFT); (2) specific strength training of the neck/shoulder muscles (SST) or (3) reference intervention without physical exercise. Electromyographic activity (EMG), tissue oxygenation (near infrared spectroscopy), and pain intensity were...... to improved oxygenation of the painful muscles. SST lowered the overall level of pain both during rest and work, possibly due to a lowered relative exposure as evidenced by a lowered relative EMG. The results demonstrate differential adaptive mechanisms of contrasting physical exercise interventions...

  11. Muscle pain induced by static contraction in rats is modulated by peripheral inflammatory mechanisms.

    Science.gov (United States)

    Santos, Diogo Francisco da Silva Dos; Melo Aquino, Bruna de; Jorge, Carolina Ocanha; Azambuja, Graciana de; Schiavuzzo, Jalile Garcia; Krimon, Suzy; Neves, Juliana Dos Santos; Parada, Carlos Amilcar; Oliveira-Fusaro, Maria Claudia Gonçalves

    2017-09-01

    Muscle pain is an important health issue and frequently related to static force exertion. The aim of this study is to evaluate whether peripheral inflammatory mechanisms are involved with static contraction-induced muscle pain in rats. To this end, we developed a model of muscle pain induced by static contraction performed by applying electrical pulses through electrodes inserted into muscle. We also evaluated the involvement of neutrophil migration, bradykinin, sympathetic amines and prostanoids. A single session of sustained static contraction of gastrocnemius muscle induced acute mechanical muscle hyperalgesia without affecting locomotor activity and with no evidence of structural damage in muscle tissue. Static contraction increased levels of creatine kinase but not lactate dehydrogenase, and induced neutrophil migration. Dexamethasone (glucocorticoid anti-inflammatory agent), DALBK (bradykinin B1 antagonist), Atenolol (β1 adrenoceptor antagonist), ICI 118,551 (β2 adrenoceptor antagonist), indomethacin (cyclooxygenase inhibitor), and fucoidan (non-specific selectin inhibitor) all reduced static contraction-induced muscle hyperalgesia; however, the bradykinin B2 antagonist, bradyzide, did not have an effect on static contraction-induced muscle hyperalgesia. Furthermore, an increased hyperalgesic response was observed when the selective bradykinin B1 agonist des-Arg(9)-bradykinin was injected into the previously stimulated muscle. Together, these findings demonstrate that static contraction induced mechanical muscle hyperalgesia in gastrocnemius muscle of rats is modulated through peripheral inflammatory mechanisms that are dependent on neutrophil migration, bradykinin, sympathetic amines and prostanoids. Considering the clinical relevance of muscle pain, we propose the present model of static contraction-induced mechanical muscle hyperalgesia as a useful tool for the study of mechanisms underlying static contraction-induced muscle pain. Copyright © 2017 IBRO

  12. Fatty muscle atrophy: prevalence in the hindfoot muscles on MR images of asymptomatic volunteers and patients with foot pain.

    Science.gov (United States)

    Schmid, Daniel T; Hodler, Juerg; Mengiardi, Bernard; Pfirrmann, Christian W A; Espinosa, Norman; Zanetti, Marco

    2009-10-01

    To determine prevalence and degree of fatty muscle atrophy in plantar foot muscles in asymptomatic volunteers and in patients with foot pain. Institutional review board approval and informed consent were obtained. The prevalence and degree of fatty muscle atrophy were evaluated with magnetic resonance imaging in the abductor digiti minimi (ADM), flexor digitorum brevis (FDB), abductor hallucis (AH), and quadratus plantae (QP) muscles in 80 asymptomatic volunteers (mean age, 48 years; range, 23-84 years) and 80 patients with foot pain (mean age, 48 years; range, 20-86 years). Muscles were characterized as normal (grade 0) or as having mild (grade 1) or substantial (grade 2) fatty atrophy by two readers separately. Results of visual grading for both readers were compared by using the Mann-Whitney test. Associations between age and degree of fatty muscle atrophy were assessed by using the Kruskal-Wallis test. Readers 1 and 2 found substantial fatty atrophy of the ADM muscle in four (5%) and five (6%) volunteers, respectively, and in three (4%) and nine (11%) patients, respectively. One reader diagnosed substantial fatty atrophy of the AH muscle in three (4%) volunteers and of the FDB muscle in two (2%) volunteers. Prevalence for the QP muscle varied between 0% and 1%. An association between age and degree of fatty atrophy of the ADM muscle was found for volunteers by both readers and for patients by reader 1 (P muscle atrophy of the ADM muscle-classically considered to represent entrapment neuropathy-is between 4% and 11% in both asymptomatic volunteers and patients with foot pain, and it increases with age.

  13. Dysfunction of endogenous pain inhibition during exercise with painful muscles in patients with shoulder myalgia and fibromyalgia.

    Science.gov (United States)

    Lannersten, Lisa; Kosek, Eva

    2010-10-01

    The aim of this study was to investigate how exercise influenced endogenous pain modulation in healthy controls, shoulder myalgia patients and fibromyalgia (FM) patients. Twenty-one healthy subjects, 20 shoulder myalgia patients and 20 FM patients, all females, participated. They performed standardized static contractions, that is, outward shoulder rotation (m. infraspinatus) and knee extension (m. quadriceps). Pressure pain thresholds (PPTs) were determined bilaterally at m. infraspinatus and m. quadriceps. During contractions PPTs were assessed at the contracting muscle, the resting homologous contralateral muscle and contralaterally at a distant site (m. infraspinatus during contraction of m. quadriceps and vice versa). Myalgia patients had lower PPTs compared to healthy controls at m. infraspinatus bilaterally (ppain regulatory mechanisms in myalgia patients during contraction of the non-afflicted m. quadriceps, but a lack of pain inhibition during contraction of the painful m. infraspinatus. FM patients failed to activate their pain inhibitory mechanisms during all contractions.

  14. Assessment of Muscle Pain Induced by Elbow-Flexor Eccentric Exercise.

    Science.gov (United States)

    Lau, Wing Yin; Blazevich, Anthony J; Newton, Michael J; Wu, Sam Shi Xuan; Nosaka, Kazunori

    2015-11-01

    Delayed-onset muscle soreness (DOMS) is a common muscle pain that many people experience and is often used as a model of acute muscle pain. Researchers have reported the effects of various interventions on DOMS, but different DOMS assessment protocols used in these studies make it difficult to compare the effects. To investigate DOMS characteristics after elbow-flexor eccentric exercise to establish a standardized DOMS assessment protocol. Descriptive laboratory study. Research laboratory. Ten healthy, untrained men (21-39 years). Participants performed 10 sets of 6 maximal isokinetic eccentric contractions of the elbow flexors. Indirect muscle-damage markers were maximal voluntary isometric contraction torque, range of motion, and serum creatine kinase activity. Muscle pain was assessed before exercise, immediately postexercise, and 1 to 5 days postexercise using (1) a visual analog scale (VAS), (2) a category ratio-10 scale (CR-10) when applying static pressure and palpation at different sites (3, 9, and 15 cm above the elbow crease), and (3) pressure-pain thresholds (PPTs) at 50 sites (pain mapping). Maximal voluntary isometric contraction and range of motion decreased and creatine kinase activity increased postexercise, indicating muscle damage. Palpation induced greater pain than static pressure, and longitudinal and transverse palpations induced greater pain than circular palpation (P exercise, but the pain-sensitive regions shifted to the central and distal regions of the biceps brachii at 1 to 3 days postexercise (P eccentric exercise.

  15. Placebo Analgesia Changes Alpha Oscillations Induced by Tonic Muscle Pain: EEG Frequency Analysis Including Data during Pain Evaluation

    Science.gov (United States)

    Li, Linling; Wang, Hui; Ke, Xijie; Liu, Xiaowu; Yuan, Yuan; Zhang, Deren; Xiong, Donglin; Qiu, Yunhai

    2016-01-01

    Placebo exhibits beneficial effects on pain perception in human experimental studies. Most of these studies demonstrate that placebo significantly decreased neural activities in pain modulatory brain regions and pain-evoked potentials. This study examined placebo analgesia-related effects on spontaneous brain oscillations. We examined placebo effects on four order-fixed 20-min conditions in two sessions: isotonic saline-induced control conditions (with/without placebo) followed by hypertonic saline-induced tonic muscle pain conditions (with/without placebo) in 19 subjects using continuous electroencephalography (EEG) recording. Placebo treatment exerted significant analgesic effects in 14 placebo responders, as subjective intensity of pain perception decreased. Frequency analyses were performed on whole continuous EEG data, data during pain perception rating and data after rating. The results in the first two cases revealed that placebo induced significant increases and a trend toward significant increases in the amplitude of alpha oscillation during tonic muscle pain compared to control conditions in frontal-central regions of the brain, respectively. Placebo-induced decreases in the subjective intensity of pain perception significantly and positively correlated with the increases in the amplitude of alpha oscillations during pain conditions. In conclusion, the modulation effect of placebo treatment was captured when the pain perception evaluating period was included. The strong correlation between the placebo effect on reported pain perception and alpha amplitude suggest that alpha oscillations in frontal-central regions serve as a cortical oscillatory basis of the placebo effect on tonic muscle pain. These results provide important evidence for the investigation of objective indicators of the placebo effect. PMID:27242501

  16. Bruksizmli bireylerin ağrılı masseter kaslarının farklı fonksiyonlardaki aktivitelerinin elektromyografi (emg ile değerlendirilmesi

    Directory of Open Access Journals (Sweden)

    Ertugrul Bolayir

    2011-11-01

    Full Text Available

    Purpose: In the present work we aimed to investigate how Bruxism caused masseter muscle pains when patients chewed hard substances such as hazelnut and how this pain affected their

    maximum clenching functions by using electromyografic (EMG techniques.

    Material and Methods: Two groups of individuals, with and without Bruxism, were investigated. All the individuals were allowed to use their right side of jaw . Pain in masseter muscles of the Bruxism patients was measured according to visual analog scala (VAS. The groups were instructed to perform two types of functions, chewing a hazelnut, 3 gr, and clenching for 15 s. While these exercises performed, activities occured in the right masseter muscles were determined by superior electromyography (EMG.

    Results: Our results indicated that both right and left masseter muscles of patients with Bruksizm showed much lessened clenching and hazelnut chewing activities than those of the control groups. The difference in the muscular activity was found to be statistically significant.

    Conclusion: Further work however appears to be necessary to substantiate that the pain per se impairs the chewing functions of Bruxism patients.

     

    ÖZET

    Amaç: Bruksizmli olguların masseter kaslarındaki ağrının, fındık  iğneme ve maksimal sıkma fonksiyonlarında kas aktivitelerini nasıl etkilediğini elektromyografik (EMG teknikle araştırmayı amaçladık.

    Materyal ve Yöntem: Araştırmamıza bruksizmli ve normal bireyler dahil edildi. Denek gruplarımızın hepsinin çiğneme sırasında aynı tarafı (sağ kullanmasına dikkat edildi. Bruksizimli olguların sağ masseter kaslarındaki ağrı VAS (visual analog skala ile belirlendi. Daha sonra bireylere yapacağı fonksiyonlar (3 gr fındık çiğneme ve 15 sn maksimal sıkma anlatıldı. Bu fonksiyonlar esnas

  17. Referred pain from trapezius muscle trigger points shares similar characteristics with chronic tension type headache.

    Science.gov (United States)

    Fernández-de-Las-Peñas, César; Ge, Hong-You; Arendt-Nielsen, Lars; Cuadrado, Maria Luz; Pareja, Juan A

    2007-05-01

    Referred pain and pain characteristics evoked from the upper trapezius muscle was investigated in 20 patients with chronic tension-type headache (CTTH) and 20 age- and gender-matched controls. A headache diary was kept for 4 weeks in order to confirm the diagnosis and record the pain history. Both upper trapezius muscles were examined for the presence of myofascial trigger points (TrPs) in a blinded fashion. The local and referred pain intensities, referred pain pattern, and pressure pain threshold (PPT) were recorded. The results show that referred pain was evoked in 85% and 50% on the dominant and non-dominant sides in CTTH patients, much higher than 55% and 25% in controls (P<0.01). Referred pain spread to the posterior-lateral aspect of the neck ipsi-lateral to the stimulated muscle in both patients and controls, with additional referral to the temple in most patients, but none in controls. Nearly half of the CTTH patients (45%) recognized the referred pain as their usual headache sensation, i.e. active TrPs. CTTH patients with active TrPs in the right upper trapezius muscle showed greater headache intensity and frequency, and longer headache duration than those with latent TrPs. CTTH patients with bilateral TrPs reported significantly decreased PPT than those with unilateral TrP (P<0.01). Our results showed that manual exploration of TrPs in the upper trapezius muscle elicited referred pain patterns in both CTTH patients and healthy subjects. In CTTH patients, the evoked referred pain and its sensory characteristics shared similar patterns as their habitual headache pain, consistent with active TrPs. Our results suggest that spatial summation of perceived pain and mechanical pain sensitivity exists in CTTH patients.

  18. Conventional versus implant-retained overlay dentures: a pilot study of masseter and anterior temporalis electromyography.

    Science.gov (United States)

    Dakhilalian, Mansour; Rismanchian, Mansour; Fazel, Akbar; Basiri, Keyvan; Azadeh, Hamid; Mahmoodi, Maryam; Fayazi, Sara; Sadr-Eshkvari, Pooyan

    2014-08-01

    Implant-supported overlay dentures (ISODs) have been widely accepted among patients using conventional removable complete dentures (CRCDs). The present study aimed to comparatively study conventional and ISODs in terms of function and coordination of masticatory muscles using electromyograms. Included were 10 patients with ISODs (each with 2 implants in the intercanine area). The mean wave range (MWR) and frequency (MWF) of masseter and temporalis were recorded with (ISOD) and without (CRCD) ball attachments while maximum clenching on cotton rolls (cotton roll clenching), maximum intercuspal clenching (clenching), and unilateral gum chewing (chewing) using electromyography. Data were analyzed in SPAW using t-paired for matched groups and independent-sample t tests for unmatched ones. The MWF differences were not statistically significant with or without attachments (P > .05). Without attachments in place, the MWF of both masseter and temporalis muscles significantly decreased when patients clenched on cotton rolls (P = .01 and .02, respectively) and when chewing unilaterally (both P = .01). With attachments present, the right and left temporalis muscles did not show identical mean wave ranges while chewing (P = .01). Without attachments, this disharmony was seen in the left and right masseter muscles (P = .03). The MWR of masseter was higher in men while chewing with attachments (P = .02). Without attachments, the MWR of temporalis was higher in women while cotton roll clenching (P = .03) and chewing (P = .02). These findings are seemingly in favor of improved masticatory function and coordination in edentulous patients with the application of ISODs.

  19. CONTRACTION CHARACTERISTICS AND MYOSIN HEAVY-CHAIN COMPOSITION OF RABBIT MASSETER MOTOR UNITS

    NARCIS (Netherlands)

    KWA, SHS; WEIJS, WA; JUCH, PJW

    1995-01-01

    1. We studied isometric twitch peak force (TPF) and twitch contraction time (TCT) of 249 motor units of the masseter muscle in 41 rabbits after extracellular electrical stimulation of single trigeminal motoneurons in the brain stem. In 41 of these units we determined the amount of tension decrease d

  20. Descending pain modulation and its interaction with peripheral sensitization following sustained isometric muscle contraction in fibromyalgia

    DEFF Research Database (Denmark)

    Ge, Hong-You; Nie, HongLing; Graven-Nielsen, Thomas

    2012-01-01

    facilitation and that the effect of descending pain modulation be dependent on peripheral muscle pain sensitivity. METHODS: Pressure pain thresholds (PPT) were measured from 13 points bilaterally in the upper trapezius muscle and from the mid-point bilaterally in the tibialis anterior before-, immediately......) than healthy control groups (286.2±24.1s) (P0.05). Following the contraction, PPTs were increased significantly and heterogeneously in the upper trapezius over time, but not, in the tibialis anterior muscle in healthy controls. However, PPT were significantly decreased over time in the tibialis...

  1. Intramuscular administration of morphine reduces mustard-oil-induced craniofacial-muscle pain behavior in lightly anesthetized rats.

    Science.gov (United States)

    Han, Seung R; Lee, Min K; Lim, Koang H; Yang, Gwi Y; Jeon, Hye J; Ju, Jin S; Yoon, Young W; Kim, Sung K; Ahn, Dong K

    2008-04-01

    The present study investigated the role of peripheral opioid receptors in mustard oil-induced nociceptive behavior and inflammation in the masseter muscles of lightly anesthetized rats. Experiments were carried out on male Sprague-Dawley rats weighing between 300 and 400 g. After initial anesthesia with sodium pentobarbital (40 mg/kg, i.p.), one femoral vein was cannulated and connected to an infusion pump for the intravenous infusion of sodium pentobarbital. The rate of infusion was adjusted to provide a constant level of anesthesia. Mustard oil (MO, 30 microl) was injected into the mid-region of the left masseter muscle via a 30-gauge needle. Intramuscularly-administered morphine significantly reduced shaking behavior but not MO-induced inflammation. Intramuscular pretreatment with naloxone, an opioid receptor antagonist, reversed antinociception produced by intramuscularly-administered morphine, while intracisternal administration of naloxone did not affect the antinociception of peripheral morphine. Pretreatment with d-Pen-Cys-Tyr-D-Trp-Orn-Thr-Pen-Thr-NH2 (CTOP), a mu opioid receptor antagonist, but not naltrindole, a delta opioid receptor antagonist, nor norbinaltorphimine (nor-BNI), a kappa opioid receptor antagonist, reversed intramuscularly-administered morphine-induced antinociception. These results indicate that intramuscularly-administered morphine produces antinociception in craniofacial muscle nociception and that this intramuscularly-administered morphine-induced antinociception is mediated by a peripheral mu opioid receptor. Our observations further support the clinical approach of administering opioids in the periphery for the treatment of craniofacial muscle nociception.

  2. The associations between pain sensitivity and knee muscle strength in healthy volunteers

    DEFF Research Database (Denmark)

    Henriksen, Marius; Klokker, Louise; Bartholdy, Cecilie

    2013-01-01

    Objectives. To investigate associations between muscle strength and pain sensitivity among healthy volunteers and associations between different pain sensitivity measures. Methods. Twenty-eight healthy volunteers (21 females) participated. Pressure pain thresholds (PPTs) were obtained from 1...... as covariates. Results. Knee extension strength was associated with computer-controlled PPT on the vastus lateralis muscle. Computer-controlled PPTs were significantly correlated between sites (r > 0.72) and with cuff PPT (r > 0.4). Saline induced pain intensity and duration were correlated between sites (r > 0.......39) and with all PPTs (r...

  3. Avaliação eletromiográfica com eletrodos de captação de superfície dos músculos masseter, temporal e bucinador de lactentes em situação de aleitamento natural e artificial Surface electromyography of facial muscles during natural and artificial feeding of infants

    Directory of Open Access Journals (Sweden)

    Cristiane F. Gomes

    2006-04-01

    Full Text Available OBJETIVO: Mensurar e comparar a atividade dos músculos masseter, temporal e bucinador em diferentes métodos de alimentação de lactentes. MÉTODO: Estudo transversal, com participação de 60 lactentes nascidos a termo e sem intercorrências, entre 2 e 3 meses de idade, divididos em três grupos: 1 aleitamento materno exclusivo; 2 aleitamento misto com uso de mamadeira; e 3 aleitamento materno exclusivo com uso de copo. Foi realizada eletromiografia com eletrodos de captação de superfície durante a alimentação. O teste estatístico utilizado é o Kruskal-Wallis, complementado com as comparações múltiplas entre pares de grupos, e todas as discussões são realizadas no nível de 5% de significância. RESULTADOS: Verificam-se maiores resultados no grupo de aleitamento materno em relação ao grupo de aleitamento por mamadeira, tanto na amplitude quanto na média de contração do músculo masseter. No que se refere ao músculo temporal, há resultados maiores na amplitude do grupo de aleitamento materno e na média de contração do grupo de aleitamento por copo, quando comparados ao grupo de aleitamento por mamadeira. Quanto ao músculo bucinador, observam-se resultados maiores no grupo de aleitamento por mamadeira com relação ao aleitamento materno, sendo que tal diferença ocorre apenas na amplitude de contração. CONCLUSÃO: As semelhanças entre a atividade muscular do grupo de aleitamento materno e aleitamento por copo permitem sugerir o uso do copo como método alternativo na alimentação de lactentes, ao contrário do aleitamento por mamadeira, devido à hiperfunção do músculo bucinador, podendo resultar em alterações motoras orais e das funções neurovegetativas.OBJECTIVE: To measure and compare the activity of the masseter, temporalis and buccinator muscles in different infant feeding methods METHODS: Cross-sectional study of 60 full-term infants with no intercurrent diseases, aged between two and three months

  4. Bilateral bony fusion around the supraspinatus muscle inducing muscle hypoplasia and shoulder pain

    Energy Technology Data Exchange (ETDEWEB)

    Son, YeNa; Jin, Wook; Park, So Young [Kyung Hee University Hospital at Gangdong, Department of Radiology, 892, Dongnam-ro, Gangdong-gu, Seoul (Korea, Republic of); Ryu, Kyung Nam; Park, Ji Seon [Kyung Hee University Hospital, Department of Radiology, 23 Kyunghee-daero, Dongdaemun-gu, Seoul (Korea, Republic of)

    2017-03-15

    We describe the case of a 30-year-old man who developed chronic bilateral shoulder pain that relapsed and remitted over the course of 1 year. The patient was diagnosed with congenital shoulder fusion anomalies. The right shoulder showed anomalous accessory articulation between the distal third of the clavicle and the acromion along with normal articulation of the shoulder on CT. At the left shoulder, bony fusions were present between the distal portion of the clavicle, the acromion, and the coracoid process, and between the coracoid process, upper portion of the glenoid, and upper body of the scapula, which formed a bony canal and was responsible for hypoplasia of the supraspinatus muscle on CT and MRI. To our knowledge, this is the first description of such congenital shoulder anomalies with extreme bony fusion and is an illustrative example of how imaging may be used to differentiate fusion from other congenital abnormalities of the shoulder to aid diagnosis. (orig.)

  5. Prevalence and anatomical location of muscle tenderness in adults with nonspecific neck/shoulder pain

    OpenAIRE

    2011-01-01

    Abstract Background Many adults experience bothersome neck/shoulder pain. While research and treatment strategies often focus on the upper trapezius, other neck/shoulder muscles may be affected as well. The aim of the present study is to evaluate the prevalence and anatomical location of muscle tenderness in adults with nonspecific neck/shoulder pain. Methods Clinical neck/shoulder examination at two large office workplaces in Copenhagen, Denmark. 174 women and 24 men (aged 25-65 years) with ...

  6. MRI assessment of paraspinal muscles in patients with acute and chronic unilateral low back pain.

    Science.gov (United States)

    Wan, Q; Lin, C; Li, X; Zeng, W; Ma, C

    2015-09-01

    To investigate the changes in paraspinal muscle cross-sectional area (CSA) and composition, using the digital data from lumbar spine MRIs of patients with acute and chronic low back pain (LBP). In total, 178 patients with unilateral LBP who had lumbar MRI examination were recruited. The data were obtained by a retrospective documentation audit. The CSAs and mean signal intensities of the bilateral paraspinal muscles [psoas major (PM), quadratus lumborum, multifidus (MF) and erector spinae (ES)] were measured, and the percentage of fat infiltration was calculated. The data between the painful side and non-painful side were compared, and between-group comparisons were tested. 42 patients with chronic unilateral LBP could indicate the problem level, and the CSA and mean signal intensity of the MF muscle were analysed at the problem level, and one vertebral above and one vertebral level below the problem level. The CSAs of the PM and ES muscles were significantly decreased in the acute LBP group, while in the chronic LBP group, significant reduction in CSA was found in the MF and ES muscles on the painful side compared with the non-painful side. The mean signal intensity and fat content of the ES muscle on the painful side in the chronic LBP group was significantly higher than that on the painful side in the acute LBP group. The significant decrease of CSA in the MF muscle was found at multiple levels on the painful side. The present findings show that there is selective ipsilateral atrophy of paraspinal muscles, specific to the symptomatic side, in patients with acute and chronic LBP. The reduction of the muscle CSA and increased fatty infiltration occurred synchronously, and the extent of change is significantly greater in chronic LBP in the ES muscle. Atrophy of the MF muscle appears to be at multiple levels but side specific in relation to symptoms in patients with chronic LBP, and the decreased muscle CSA may occur prior to fatty infiltration. There are specific

  7. Injection of adjuvant but not acidic saline into craniofacial muscle evokes nociceptive behaviors and neuropeptide expression.

    Science.gov (United States)

    Ambalavanar, R; Yallampalli, C; Yallampalli, U; Dessem, D

    2007-11-09

    Craniofacial muscle pain including muscular temporomandibular disorders accounts for a substantial portion of all pain perceived in the head and neck region. In spite of its high clinical prevalence, the mechanisms of chronic craniofacial muscle pain are not well understood. Injection of acidic saline into rodent hindlimb muscles produces pathologies which resemble muscular pathologies in chronic pain patients. Here we investigated whether analogous transformations occur following repeated injections of acidic saline into the rat masseter muscle. Injection of acidic saline (pH 4) into the masseter muscle transiently lowered i.m. pH to levels comparable to those reported for rodent hindlimb muscles. Nevertheless, repeated unilateral or bilateral injections of acidic saline (pH 4) into the masseter muscle failed to alter nociceptive behavioral responses as occurs in the hindlimb. Changing the pH of injected saline to pH 3.0 or 5.0 also did not evoke nocifensive behavior. Acid sensing ion channel 3 receptors, which are implicated in transformations following acidification of hindlimb muscles, were found on trigeminal ganglion muscle afferent neurons via combined neuronal tracing and immunocytochemistry. In contrast to the acidic saline, injection of complete Freund's adjuvant (CFA) into the masseter muscle induced mechanical allodynia for 3 weeks, thermal hyperalgesia for 1 week and an increase in the number of calcitonin gene-related peptide (CGRP)-immunoreactive muscle afferent neurons in the trigeminal ganglion. Although pH may alter CGRP release in primary afferent neurons, the number of CGRP-muscle afferent neurons did not change following i.m. injection of acidic saline. Further, there was no change in ganglionic iCGRP levels at 1, 4 or 12 days after i.m. injection of acidic saline. While these findings extend our earlier reports that CFA-induced muscle inflammation results in behavioral and neuropeptide changes they further suggest that i.m. acidification in

  8. Muscle Power Is an Independent Determinant of Pain and Quality of Life in Knee Osteoarthritis.

    Science.gov (United States)

    Reid, Kieran F; Price, Lori Lyn; Harvey, William F; Driban, Jeffrey B; Hau, Cynthia; Fielding, Roger A; Wang, Chenchen

    2015-12-01

    This study examined the relationships between leg muscle strength, power, and perceived disease severity in subjects with knee osteoarthritis (OA) in order to determine whether dynamic leg extensor muscle power would be associated with pain and quality of life in knee OA. Baseline data on 190 subjects with knee OA (mean ± SD age 60.2 ± 10.4 years, body mass index 32.7 ± 7.2 kg/m(2) ) were obtained from a randomized controlled trial. Knee pain was measured using the Western Ontario and McMaster Universities Osteoarthritis Index, and health-related quality of life was assessed using the Short Form 36 (SF-36). One-repetition maximum (1RM) strength was assessed using the bilateral leg press, and peak muscle power was measured during 5 maximum voluntary velocity repetitions at 40% and 70% of 1RM. In univariate analysis, greater muscle power was significantly associated with pain (r = -0.17, P muscle power was a significant independent predictor of pain (P ≤ 0.05) and PCS scores (P ≤ 0.04). However, muscle strength was not an independent determinant of pain or quality of life (P ≥ 0.06). Muscle power is an independent determinant of pain and quality of life in knee OA. Compared to strength, muscle power may be a more clinically important measure of muscle function within this population. New trials to systematically examine the impact of muscle power training interventions on disease severity in knee OA are particularly warranted. © 2015, American College of Rheumatology.

  9. The effects of kinesio taping on architecture, strength and pain of muscles in delayed onset muscle soreness of biceps brachii.

    Science.gov (United States)

    Lee, Yong Sin; Bae, Sea Hyun; Hwang, Jin Ah; Kim, Kyung Yoon

    2015-02-01

    [Purpose] This study aimed to confirm the effects of kinesio taping (KT) on muscle function and pain due to delayed onset muscle soreness (DOMS) of the biceps brachii. [Subjects and Methods] Thirty-seven subjects with induced DOMS were randomized into either Group I (control, n=19) or Group II (KT, n=18). Outcome measures were recorded before the intervention (application of KT) and at 24, 48, and 72 hours after the intervention. DOMS was induced, and muscle thickness was measured using ultrasonic radiography. Maximal voluntary isometric contraction (%MVIC) was measured via electromyography (EMG). Subjective pain was measured using a visual analogue scale (VAS). [Results] Group I exhibited a positive correlation between muscle thickness and elapsed time from intervention (24, 48, and 72 hours post induction of DOMS); they also showed a significant decrease in MVIC(%). Group II showed significant increases in muscle thickness up to the 48-hour interval post induction of DOMS, along with a significant decrease in MVIC (%). However, in contrast to Group I, Group II did not show a significant difference in muscle thickness or MVIC (%) at the 72-hour interval in comparison with the values prior to DOMS induction. [Conclusion] In adults with DOMS, activation of muscles by applying KT was found to be an effective and faster method of recovering muscle strength than rest alone.

  10. Fibrin sealant reduces pain after tonsillectomy: prospective randomized study.

    Science.gov (United States)

    Vaiman, Michael; Krakovski, Daniel; Gavriel, Haim

    2006-07-01

    Postsurgical pain in adults following tonsillectomy with fibrin sealant or electrocoagulation was assessed by surface electromyography (sEMG), a dysphagia severity rating scale (DSRS), and a visual analog scale (VAS) pain For group 1 (n = 40), hemostasis was achieved by fibrin sealant spraying to the tonsillar fossae. For group 2 (n = 40), hemostasis was achieved by bipolar or needle point electrocautery. The timing of single swallowing and continuous drinking and the mean electrical activity of the masseter, infrahyoid, and submental-submandibular muscles were compared with a normative database during 30 days and with DSRS and VAS scores. Electrical activity of the masseter and infrahyoid muscles was significantly higher in both groups in comparison with the normative database (p sEMG, DSRS, and VAS assessment showed that tonsillectomy ended with sealant causes less pain than electrocoagulation (p sEMG records, whereas the VAS pain score was less informative. The combined sEMG and pain score data indicate that the electrocautery hemostatic technique is more painful and traumatic than the sealant technique. Surface electromyography of swallowing is a simple, reliable evaluation method for postsurgical odynophagia complaints and might be used as an objective tool for pain assessment.

  11. Low intensity laser therapy in the treatment of the temporomandibular and masticatory muscles disease: electromyography, biometrical and pain evaluation; Terapia laser em baixa intensidade no tratamento da dor e disfuncao da articulacao temporomandibular e dos musculos mastigatorios: analise eletromiografica, biometrica e de dor

    Energy Technology Data Exchange (ETDEWEB)

    Eduardo, Luis Ricardo de Paula

    2001-07-01

    A sample of 11 patients showing temporomandibular joint disease, in one or both sides, was selected. Clinical examinations were performed on patients to define which side was the most compromised by the disease. Only the worst side was chosen to be treated by the laser therapy. The laser unit used was a diode laser (Al-Ga-As) which the wave length was 810 nm (infra-red spectrum). Irradiations were done in tree points of TMJ, with 22,5 J/cm{sup 2}; two points in the masseter muscle, with 15 J/cm{sup 2}; and tree points in the temporal muscle, with 7,5 J/cm{sup 2}. All points were irradiated for 30 seconds. The other side, of lesser complain, received a sham therapy. Patients answered to a questionnaire about the level of pain they were suffering just before and after each irradiation. Besides that mouth opening was measured, from the central lower incisor to the upper central incisor, before and after the therapy , using a digital calliper. The treatment was done during two weeks, tree irradiations with 48 hours interval in the first week, and two irradiations with the same interval in the second week. The electromyography evaluation of the masseter and anterior temporal muscles was done before and after the first irradiation and before and after the last irradiation. Patients reported improvement in relation to the level of pain, mainly after the forth irradiation, and the level of pain decreased until the last day of treatment. In relation to the degree of mouth opening, the majority of patients showed a significant increase, mainly after the fifth day of irradiation. In regard to the electromyography results, we could notice that for the temporal anterior muscle there was a tendency of improvement in the electromyographic pattern, when comparing the treated side to the non-treated side , but there were not significant results. In relation to the masseter muscles we could not see any significant results between both sides. (author)

  12. Short Term Effects of Mobilization Techniques on Neck Pain and Deep Neck Flexor Muscle Endurance in Patients with Mechanical Chronic Neck Pain

    OpenAIRE

    Kılınç, Hasan Erkan; Harput, Gülcan; Baltacı, Gül; İnce, Deniz İnal

    2014-01-01

    Objectives: The aim of the study was to investigate short term effects of cervical and scapular mobilization techniques on neck pain and deep cervical muscles endurance in chronical mechanical neck pain patients. Methods: 22 chronical mechanic neck pain patients four male 18 female (mean age: mean±sd 35.59± 15.85) were included. Before treatment, neck pain level (visual analog scale) and deep neck flexor muscles endurance (in supine position with digital chronometer) of all patients were eval...

  13. Negative affect, pain and disability in osteoarthritis patients: the mediating role of muscle weakness.

    NARCIS (Netherlands)

    Dekker, J.; Tola, P.; Aufdemkampe, G.; Winckers, M.

    1993-01-01

    Negative affect has been shown to be associated with high levels of pain and disability in osteoarthritis (OA) patients. As an explanation of this association, it was hypothesized that muscle weakness is a mediating factor between negative affect, pain and disability. Accordingly, negative affect

  14. Low back pain characterized by muscle resistance and occupational factors associated with nursing

    Directory of Open Access Journals (Sweden)

    Rafael de Souza Petersen

    2014-06-01

    Full Text Available OBJECTIVE: to identify the occupational factors associated with low back pain using a surveillance tool and to characterize the low back pain by the resistance of the extensor muscles of the vertebral column among nursing professionals at an Intensive Care Unit.METHODS: Cross-sectional study. The workers answered a questionnaire about occupational factors and participated in a resistance test of the extensor muscles of the vertebral column. Associations were established through Student's T-test or Mann-Whitney's U-test and correlations using Pearson's test.RESULTS: Out of 48 participants, 32 (67% suffered from low pain. For the resistance test, the subjects suffering from low back pain endured less time in comparison with asymptomatic subjects, but without significant differences (p=0.147. The duration of the pain episode showed a significant negative correlation (p=0.016 with the results of the resistance test though. The main factors identified as causes of low back pain were biomechanical and postural elements, conditions of the muscle structure and physical and organizational conditions.CONCLUSIONS: the main occupational factors associated with the low back pain were the posture and the characteristics of the physical and organizational conditions. In addition, the extensor muscles of the column showed a trend towards lesser resistance for workers in pain. This evidence is important when considering prevention and treatment strategies.

  15. Motor adaptations to local muscle pain during a bilateral cyclic task.

    Science.gov (United States)

    Brøchner Nielsen, Niels-Peter; Tucker, Kylie; Dorel, Sylvain; Guével, Arnaud; Hug, François

    2017-02-01

    The aim of this study was to determine how unilateral pain, induced in two knee extensor muscles, affects muscle coordination during a bilateral pedaling task. Fifteen participants performed a 4-min pedaling task at 130 W in two conditions (Baseline and Pain). Pain was induced by injection of hypertonic saline into the vastus medialis (VM) and vastus lateralis (VL) muscles of one leg. Force applied throughout the pedaling cycle was measured using an instrumented pedal and used to calculate pedal power. Surface electromyography (EMG) was recorded bilaterally from eight muscles to assess changes in muscle activation strategies. Compared to Baseline, during the Pain condition, EMG amplitude of muscles of the painful leg (VL and VM-the painful muscles, and RF-another quadriceps muscle with no pain) was lower during the extension phase [(mean ± SD): VL: -22.5 ± 18.9%; P < 0.001; VM: -28.8 ± 19.9%; P < 0.001, RF: -20.2 ± 13.9%; P < 0.001]. Consistent with this, pedal power applied by the painful leg was also lower during the extension phase (-16.8 ± 14.2 W, P = 0.001) during Pain compared to Baseline. This decrease was compensated for by an 11.3 ± 8.1 W increase in pedal power applied by the non-painful leg during its extension phase (P = 0.04). These results support pain adaptation theories, which suggest that when there is a clear opportunity to compensate, motor adaptations to pain occur to decrease load within the painful tissue. Although the pedaling task offered numerous possibilities for compensation, only between-leg compensations were systematically observed. This finding is discussed in relation to the mechanical and neural constraints of the pedaling task.

  16. Torque-EMG-velocity relationship in female workers with chronic neck muscle pain

    DEFF Research Database (Denmark)

    Andersen, Lars L; Nielsen, Pernille K; Søgaard, Karen

    2008-01-01

    The present study investigated the effect of chronic neck muscle pain (defined as trapezius myalgia) on neck/shoulder muscle function during concentric, eccentric and static contraction. Forty-two female office workers with trapezius myalgia (MYA) and 20 healthy matched controls (CON) participated...

  17. Muscle power is an independent determinant of pain and quality of life in knee osteoarthritis

    Science.gov (United States)

    OBJECTIVE: This study examined the relationships between leg muscle strength, power, and perceived disease severity in subjects with knee osteoarthritis (OA) in order to determine whether dynamic leg extensor muscle power would be associated with pain and quality of life in knee OA. METHODS: Baseli...

  18. A Patient Developed Painful Muscle Cramps due to Overeating Mangos

    Directory of Open Access Journals (Sweden)

    Kazuo Abe

    2012-01-01

    Full Text Available A 79-year-old woman had a habit to eat a mango every night before sleep and experienced muscle cramps during sleep. Her muscle cramps may be resulted from potassium overload due to overeating mangos.

  19. Dry needling of the trapezius muscle in office workers with neck pain: a randomized clinical trial.

    Science.gov (United States)

    Cerezo-Téllez, Ester; Lacomba, María Torres; Fuentes-Gallardo, Isabel; Mayoral Del Moral, Orlando; Rodrigo-Medina, Beatriz; Gutiérrez Ortega, Carlos

    2016-09-01

    Neck pain is a frequent complaint in office workers. This pain can be caused by myofascial trigger points (MTrPs) in the trapezius muscle. This study aimed to determine the effectiveness of deep dry needling (DDN) of active MTrPs in the trapezius muscle. A randomized, single blinded clinical trial was carried out at the Physical Therapy Department at Physiotherapy in Women's Health Research Group at Physical Therapy Department of University of Alcalá, in Alcalá de Henares, Madrid, Spain. Forty-four office workers with neck pain and active MTrPs in the trapezius muscle were randomly allocated to either the DDN or the control group (CG). The participants in the DDN group were treated with DDN of all MTrPs found in the trapezius muscle. They also received passive stretch of the trapezius muscle. The CG received the same passive stretch of the trapezius muscle only. The primary outcome measure was subjective pain intensity, measured using a visual analogue scale (VAS). Secondary outcomes were pressure pain threshold (PPT), cervical range of motion (CROM) and muscle strength. Data were collected at baseline, after interventions and 15 days after the last treatment. Differences were found between the DDN group and the CG for the VAS (P dry needling and passive stretch seems to be more effective than passive stretch only. The effects are maintained in the short term. The results support the use of DDN in the management of trapezius muscle myofascial pain syndrome in neck pain.

  20. Clinical effects of deep cervical flexor muscle activation in patients with chronic neck pain

    OpenAIRE

    2016-01-01

    [Purpose] The purpose of this study was to investigate clinical effects of deep cervical flexor (DCF) muscles exercise on pain, Neck Disability Index (NDI), and neck and shoulder postures in patients with chronic neck pain. [Subjects and Methods] Twenty-eight patients with chronic neck pain were randomly assigned into either the general strengthening exercise (GSE) group or the DCF activation group as control and experimental groups, respectively. All exercises were performed three times per ...

  1. Do cerebral potentials to magnetic stimulation of paraspinal muscles reflect changes in palpable muscle spasm, low back pain, and activity scores?

    OpenAIRE

    Zhu, Y.; Haldeman, S.; Hsieh, CYJ; Wu, P; Starr, A.

    2000-01-01

    Objective: Previous studies have shown that cortical-evoked potentials on magnetic stimulation of muscles are influenced by muscle contraction, vibration, and muscle spasm. This study was carried out to determine whether these potentials correlate with palpatory muscle spasm, patient symptoms, and disability in patients with low back pain. Methods: A prospective observational study was performed on 13 subjects with a history of low back pain visiting an orthopedic hospital-based clinic. Patie...

  2. Entropy measures of back muscles EMG for subjects with and without pain

    Science.gov (United States)

    Zurcher, Ulrich; Kaufman, Miron; Vyhnalek, Bryan; Sung, Paul

    2007-10-01

    We have previously reported that the time-dependent entropy S(t) calculated from electromyography time series of low back muscles exhibit plateau-like behavior for intermediate times [50 ,ms low back pain [J. Rehab. Res. Dev. 44, 599 (2007)]. We report results of a larger study, and compare the entropies for the left -and right thoracic and left- and right lumbar muscles. We also compare entropies from muscles before and after physical therapy intervention.

  3. Two unusual cases of external rotator muscle pathology producing hip pain

    Directory of Open Access Journals (Sweden)

    Graeme Thompson

    2015-03-01

    Full Text Available Two unusual cases of inflammation of the external rotator muscles of the hip are presented. In each case, the patient presented with acute hip pain. The diagnoses of acute calcific periarthritis involving the gluteus medius muscle, and pyomyositis of the obturator internus muscle secondary to a perianal fistula, were made with the aid of diagnostic imaging and histology. The importance of reviewing the pelvic viscera is highlighted.

  4. Are MRI-defined fat infiltrations in the multifidus muscles associated with low back pain?

    DEFF Research Database (Denmark)

    Kjær, Per; Bendix, Tom; Sorensen, Joan Solgaard

    2007-01-01

    Because training of the lumbar muscles is a commonly recommended intervention in low back pain (LBP), it is important to clarify whether lumbar muscle atrophy is related to LBP. Fat infiltration seems to be a late stage of muscular degeneration, and can be measured in a non-invasive manner using...... magnetic resonance imaging. The purpose of this study was to investigate if fat infiltration in the lumbar multifidus muscles (LMM) is associated with LBP in adults and adolescents....

  5. Effects of unilateral and bilateral experimental low-back pain on trunk muscle activity during stair walking in healthy and recurrent low-back pain patients

    DEFF Research Database (Denmark)

    Larsen, Lars Henrik; Hirata, Rogerio Pessoto; Graven-Nielsen, Thomas

    2016-01-01

    Aim To explore the trunk muscle activity in healthy and recurrent low back pain (R-LBP) patients with no present pain during stair ascent and descent before and after unilateral and bilateral experimental low back pain (LBP). Methods Twenty-five healthy controls and 25 pain-free R-LBP patients...... in m. rectus abdominis during all phases, with larger decrease during bilateral compared with unilateral pain (Ppain in the back muscles (P....04). Conclusions The impact of unilateral and bilateral experimental LBP on trunk muscle activity was different between healthy participants and R-LBP patients. Pain resulted in increased trunk muscle activity in healthy, while R-LBP patients decreased the back and increased the abdominal muscle activity. However...

  6. The smart Peano fluidic muscle: a low profile flexible orthosis actuator that feels pain

    Science.gov (United States)

    Veale, Allan J.; Anderson, Iain A.; Xie, Shane Q.

    2015-03-01

    Robotic orthoses have the potential to provide effective rehabilitation while overcoming the availability and cost constraints of therapists. These orthoses must be characterized by the naturally safe, reliable, and controlled motion of a human therapist's muscles. Such characteristics are only possible in the natural kingdom through the pain sensing realized by the interaction of an intelligent nervous system and muscles' embedded sensing organs. McKibben fluidic muscles or pneumatic muscle actuators (PMAs) are a popular orthosis actuator because of their inherent compliance, high force, and muscle-like load-displacement characteristics. However, the circular cross-section of PMA increases their profile. PMA are also notoriously unreliable and difficult to control, lacking the intelligent pain sensing systems of their biological muscle counterparts. Here the Peano fluidic muscle, a new low profile yet high-force soft actuator is introduced. This muscle is smart, featuring bioinspired embedded pressure and soft capacitive strain sensors. Given this pressure and strain feedback, experimental validation shows that a lumped parameter model based on the muscle geometry and material parameters can be used to predict its force for quasistatic motion with an average error of 10 - 15N. Combining this with a force threshold pain sensing algorithm sets a precedent for flexible orthosis actuation that uses embedded sensors to prevent damage to the actuator and its environment.

  7. Muscle fatigue in relation to forearm pain and tenderness among professional computer users

    DEFF Research Database (Denmark)

    Thomsen, GF; Johnson, PW; Svendsen, Susanne Wulff

    2007-01-01

    and twenty gender and age matched referents without such complaints were enrolled from the Danish NUDATA study of neck and upper extremity disorders among technical assistants and machine technicians. Fatigue of the right forearm extensor muscles was assessed by muscle twitch forces in response to low...... response was not explained by differences in the MVC or body mass index. CONCLUSION: Computer users with forearm pain and moderate to severe palpation tenderness had diminished forearm extensor muscle fatigue response. Additional studies are necessary to determine whether this result reflects an adaptive...... response to exposure without any pathophysiological significance, or represents a part of a causal pathway leading to pain....

  8. Association of low back pain with muscle stiffness and muscle mass of the lumbar back muscles, and sagittal spinal alignment in young and middle-aged medical workers.

    Science.gov (United States)

    Masaki, Mitsuhiro; Aoyama, Tomoki; Murakami, Takashi; Yanase, Ko; Ji, Xiang; Tateuchi, Hiroshige; Ichihashi, Noriaki

    2017-09-14

    Muscle stiffness of the lumbar back muscles in low back pain (LBP) patients has not been clearly elucidated because quantitative assessment of the stiffness of individual muscles was conventionally difficult. This study aimed to examine the association of LBP with muscle stiffness assessed using ultrasonic shear wave elastography (SWE) and muscle mass of the lumbar back muscle, and spinal alignment in young and middle-aged medical workers. The study comprised 23 asymptomatic medical workers [control (CTR) group] and 9 medical workers with LBP (LBP group). Muscle stiffness and mass of the lumbar back muscles (lumbar erector spinae, multifidus, and quadratus lumborum) in the prone position were measured using ultrasonic SWE. Sagittal spinal alignment in the standing and prone positions was measured using a Spinal Mouse. The association with LBP was investigated by multiple logistic regression analysis with a forward selection method. The analysis was conducted using the shear elastic modulus and muscle thickness of the lumbar back muscles, and spinal alignment, age, body height, body weight, and sex as independent variables. Multiple logistic regression analysis showed that muscle stiffness of the lumbar multifidus muscle and body height were significant and independent determinants of LBP, but that muscle mass and spinal alignment were not. Muscle stiffness of the lumbar multifidus muscle in the LBP group was significantly higher than that in the CTR group. The results of this study suggest that LBP is associated with muscle stiffness of the lumbar multifidus muscle in young and middle-aged medical workers. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Function and structure of the deep cervical extensor muscles in patients with neck pain.

    Science.gov (United States)

    Schomacher, Jochen; Falla, Deborah

    2013-10-01

    The deep cervical extensors are anatomically able to control segmental movements of the cervical spine in concert with the deep cervical flexors. Several investigations have confirmed changes in cervical flexor muscle control in patients with neck pain and as a result, effective evidence-based therapeutic exercises have been developed to address such dysfunctions. However, knowledge on how the deep extensor muscles behave in patients with neck pain disorders is scare. Structural changes such as higher concentration of fat within the muscle, variable cross-sectional area and higher proportions of type II fibres have been observed in the deep cervical extensors of patients with neck pain compared to healthy controls. These findings suggest that the behaviour of the deep extensors may be altered in patients with neck pain. Consistent with this hypothesis, a recent series of studies confirm that patients display reduced activation of the deep cervical extensors as well as less defined activation patterns. This article provides an overview of the various different structural and functional changes in the deep neck extensor muscles documented in patients with neck pain. Relevant recommendations for the management of muscle dysfunction in patients with neck pain are presented.

  10. Treatment of chronic pain associated with nocturnal bruxism with botulinum toxin. A prospective and randomized clinical study

    Science.gov (United States)

    Al-Wayli, Hessa

    2017-01-01

    Background To evaluate the role of botulinum toxin type A (BTX-A) in the treatment of pain associated with nocturnal bruxism. Material and Methods Fifty subjects reporting nocturnal bruxism were recruited for a randomized clinical trial. Twenty five bruxers were injected with botulinum toxin in both masseters, and twenty five were treated with traditional methods of treating bruxism. Patients were evaluated at 3rd week, 2nd and 6th month and one year after injection and then used to calculate bruxism events. Bruxism symptoms were investigated using questionnaires. Results Mean pain score due to Bruxism events in the masseter muscle decreased significantly in the botulinum toxin injection group A (P =0.000, highly significant). However, in the conventional treatment group, mean pain score does not show improvement with time (p>0.05). Conclusions Our results suggest that botulinum toxin injection reduced the mean pain score and number of bruxism events, most likely by decreasing the muscle activity of masseter rather than affecting the central nervous system. Key words:Temporomandibular pain, nocturnal bruxism, botulinum toxin.

  11. Clinical features in patients with chronic muscle pain--with special reference to fibromyalgia

    DEFF Research Database (Denmark)

    Jacobsen, Søren; Petersen, I S; Danneskiold-Samsøe, B

    1993-01-01

    Clinical characteristics were studied in patients with chronic muscle pain, divided into three groups according to the characteristics of their pain; "fibromyalgia" (n = 23), "widespread muscle pain" (n = 21), and "regional muscle pain" (n = 28). Typical fibromyalgia features were also seen in th...... justify the current classification of fibromyalgia at this stage....... in the other groups of patients, but not to the same extent. In particular, sleep disturbance, subjective swelling, cold and exercise intolerance and low self-reported physical performance were significantly related to fibromyalgia. The major components of fibromyalgia were not wholly different compared...... with other European and North American studies, except for sleep disturbance and subjective swelling, which was somewhat more pronounced in this study. The most used medications in fibromyalgia patients at referral were analgesics, anxiolytic drugs and female sex hormones. Medication in fibromyalgia...

  12. An increased response to experimental muscle pain is related to psychological status in women with chronic non-traumatic neck-shoulder pain

    Directory of Open Access Journals (Sweden)

    Persson Ann L

    2011-10-01

    Full Text Available Abstract Background Neck-shoulder pain conditions, e.g., chronic trapezius myalgia, have been associated with sensory disturbances such as increased sensitivity to experimentally induced pain. This study investigated pain sensitivity in terms of bilateral pressure pain thresholds over the trapezius and tibialis anterior muscles and pain responses after a unilateral hypertonic saline infusion into the right legs tibialis anterior muscle and related those parameters to intensity and area size of the clinical pain and to psychological factors (sleeping problems, depression, anxiety, catastrophizing and fear-avoidance. Methods Nineteen women with chronic non-traumatic neck-shoulder pain but without simultaneous anatomically widespread clinical pain (NSP and 30 age-matched pain-free female control subjects (CON participated in the study. Results NSP had lower pressure pain thresholds over the trapezius and over the tibialis anterior muscles and experienced hypertonic saline-evoked pain in the tibialis anterior muscle to be significantly more intense and locally more widespread than CON. More intense symptoms of anxiety and depression together with a higher disability level were associated with increased pain responses to experimental pain induction and a larger area size of the clinical neck-shoulder pain at its worst. Conclusion These results indicate that central mechanisms e.g., central sensitization and altered descending control, are involved in chronic neck-shoulder pain since sensory hypersensitivity was found in areas distant to the site of clinical pain. Psychological status was found to interact with the perception, intensity, duration and distribution of induced pain (hypertonic saline together with the spreading of clinical pain. The duration and intensity of pain correlated negatively with pressure pain thresholds.

  13. Uncovering the biochemical milieu of myofascial trigger points using in vivo microdialysis: an application of muscle pain concepts to myofascial pain syndrome.

    Science.gov (United States)

    Shah, Jay P; Gilliams, Elizabeth A

    2008-10-01

    This article discusses muscle pain concepts in the context of myofascial pain syndrome (MPS) and summarizes microdialysis studies that have surveyed the biochemical basis of this musculoskeletal pain condition. Though MPS is a common type of non-articular pain, its pathophysiology is only beginning to be understood due to its enormous complexity. MPS is characterized by the presence of myofascial trigger points (MTrPs), which are defined as hyperirritable nodules located within a taut band of skeletal muscle. MTrPs may be active (spontaneously painful and symptomatic) or latent (non-spontaneously painful). Painful MTrPs activate muscle nociceptors that, upon sustained noxious stimulation, initiate motor and sensory changes in the peripheral and central nervous systems. This process is called sensitization. In order to investigate the peripheral factors that influence the sensitization process, a microdialysis technique was developed to quantitatively measure the biochemical milieu of skeletal muscle. Biochemical differences were found between active and latent MTrPs, as well as in comparison with healthy muscle tissue. In this paper we relate the findings of elevated levels of sensitizing substances within painful muscle to the current theoretical framework of muscle pain and MTrP development.

  14. [DIAGNOSTICS OF POSITION OF THE MOTOR AND TRIGGER POINTS: OF THE CHEWING MUSCLES FOR ZYGOMATIC COMPLEX FRACTURES].

    Science.gov (United States)

    Malanchuk, V O; Volovar, O S; Timoshchenko, N M; Kostiuk, T M

    2015-01-01

    Existing treatment methods of zygomatic complex fractures, which are complicated by contrac- ture of the masseter as a result of displaced bone fragments, have to be improved. Lack of muscle relaxation leads to the formation of local hypertonicity. In spasmodic muscle fibers varies perfusion and hypoxia occurs, which is accompanied by the release of inflammatory mediators and activation of pain receptors. Over time, areas formed local hypertonicity specific trigger points that contain multiple sensory loci and include one or more sensitive nerve endings. A device for the effective electromyographic study of masseters as a source of their condition and the dynamics of changes in masticatory muscles during patient treatment by improving the fixation system on the face of the patient and the introduction of more perfect spatial coordinate system for mathematical calculations masseter motor position (or triggered) point. Patients were examined before and in the dynamics of treatment according to our methodology, which included proper masseter relaxation, reposition and fixation of bone fragments and further medical therapy.

  15. Effects of deep and superficial experimentally induced acute pain on muscle sympathetic nerve activity in human subjects

    National Research Council Canada - National Science Library

    A. R. Burton; I. Birznieks; P. S. Bolton; L. A. Henderson; V. G. Macefield

    2009-01-01

    ...), whereas deep pain is believed to cause vasodepression. To date, no studies have addressed whether deep or superficial pain produces such differential effects on muscle sympathetic nerve activity (MSNA...

  16. Pain and tenderness in human temporal muscle induced by bradykinin and 5-hydroxytryptamine

    DEFF Research Database (Denmark)

    Jensen, Kai; Tuxen, C; Pedersen-Bjergaard, U

    1990-01-01

    Pain was induced in 19 healthy individuals by double-blind injections into the temporal muscle of 0.2 ml of physiological saline with or without active substances added. 5-Hydroxytryptamine (2 nmol) caused pain similar to saline, bradykinin (2 nmol) only insignificantly more pain (0.05 less than p...... less than 0.1), while a mixture of the two substances in half dosage (1 nmol + 1 nmol) caused pain significantly above saline (p less than 0.01). Variations in the response to saline did not permit a conclusion to be made on the question of induced tenderness. However, the mixture of the two substances...

  17. The psoas muscle as cause of low back pain in infantile cerebral palsy.

    Science.gov (United States)

    Marrè-Brunenghi, G; Camoriano, R; Valle, M; Boero, S

    2008-03-01

    Psoas muscle spasticity is hypothesised as a rare cause of low back pain in patients with infantile cerebral palsy. The authors describe a new manoeuvre for the study of psoas tenderness and ultrasound (US)-guided transabdominal botulinum toxin injection technique. A possible causal relationship between psoas tension and low back pain was found incidentally in two examined cases. In subsequent patients, botulinum toxin was injected and, in cases of disappearance of symptoms, the psoas tendon was sectioned at the pelvic brim with definitive disappearance of pain. The relationship between psoas tension and low back pain in patients with infantile cerebral palsy seems likely, given the result in the four patients.

  18. Muscle relaxation for individuals having tattoos removed through laser treatment: possible effects regarding anxiety and pain.

    Science.gov (United States)

    Huang, Faye; Chou, Wen-Jiun; Chen, Tien-Hsing; Chen, Ching; Hsieh, Yu-Lian; Chong, Mian-Yoon; Hung, Chi-Fa; Lin, Shu-Ching; Tsai, Hsiu-Huang; Wang, Liang-Jen

    2016-08-01

    Effectively managing pain is vital for the well-being and satisfaction of patients undergoing dermatologic treatments involving lasers. This study investigates the potential outcome of using muscle relaxation techniques to reduce pain among people having their tattoos removed with laser treatment. This study consists of 56 participants (mean age 18.1 ± 2.1 years) that had tattoos removed using the principle of selective photothermolysis. These participants underwent muscle relaxation before receiving the laser treatment. Their peripheral skin temperatures (PST) were measured both at the beginning and the end of the muscle relaxation period. Then, the Beck Anxiety Inventory was applied to evaluate anxiety levels. Once the laser treatment was completed, pain levels were measured using a visual analogue scale. A total of 125 person-sessions of laser treatment and psychometric assessments were performed in this study. The muscle relaxation method significantly increased the PST of the participants while reducing the levels of anxiety and pain throughout the course of the laser treatment procedure. The PST, anxiety scores, and pain scores all showed significant correlations with one another. According to the results obtained, this study proposes that muscle relaxation techniques be considered possibly auxiliary treatment options for individuals having tattoos removed through laser treatment. Additional studies with a comparison group and a larger sample size are required in the future to confirm the effectiveness of such intervention.

  19. Treatment experience of pulsed radiofrequency under ultrasound guided to the trapezius muscle at myofascial pain syndrome -a case report-.

    Science.gov (United States)

    Park, Chung Hoon; Lee, Yoon Woo; Kim, Yong Chan; Moon, Joo Hwa; Choi, Jong Bum

    2012-01-01

    Trigger point injection treatment is an effective and widely applied treatment for myofascial pain syndrome. The trapezius muscle frequently causes myofascial pain in neck area. We herein report a case in which direct pulsed radiofrequency (RF) treatment was applied to the trapezius muscle. We observed that the RF treatment produced continuous pain relief when the effective duration of trigger point injection was temporary in myofascial pain.

  20. Asymmetric muscle function in patients with developmental mandibular asymmetry.

    Science.gov (United States)

    Dong, Y; Wang, X M; Wang, M Q; Widmalm, S E

    2008-01-01

    The aim was to test the hypothesis that developmental mandibular asymmetry is associated with increased asymmetry in muscle activity. Patients with mandibular condylar and/or ramus hyperplasia having unilateral cross-bite were compared with healthy subjects with normal occlusion. Muscle activity was recorded with surface electrodes in the masseter, suprahyoid, sternocleidomastoid muscle (SCM) and upper trapezius areas during jaw opening-closing-clenching, head-neck flexion-extension, and elevation-lowering of shoulders. Root mean square (RMS) and mean power frequency (MPF) values were calculated and analysed using anova and t-tests with P masseter muscles showed co-activation during jaw and head movements, significantly more asymmetric in the patients than in the healthy subjects. The RMS and MPF values were higher in the patients than in the controls in the SCM and suprahyoid areas on both sides during jaw opening-closing movement. The results indicate that the ability to perform symmetric jaw and neck muscle activities is disturbed in patients with developmental mandibular asymmetry. This is of clinical interest because asymmetric activity may be an etiologic factor in temporomandibular joint and cervical pain. The results support that co-activation occurs between jaw and neck muscles during voluntary jaw opening and indicate that postural antigravity reflex activity occurs in the masseter area during head extension. Further studies, where EMG recordings are made from the DMA patients at early stages are motivated to verify activity sources and test if the asymmetric activity is associated with muscle and joint pain in the jaw and cervical areas.

  1. Modulation of motor variability related to experimental muscle pain during elbow-flexion contractions.

    Science.gov (United States)

    Mista, Christian A; Christensen, Steffan W; Graven-Nielsen, Thomas

    2015-02-01

    Experimental muscle pain typically reorganizes the motor control. The pain effects may decrease when the three-dimensional force components are voluntarily adjusted, but it is not known if this could have negative consequences on other structures of the motor system. The present study assessed the effects of acute pain on the force variability during sustained elbow flexion when controlling task-related (one-dimensional) and all (three-dimensional) contraction force components via visual feedback. Experimental muscle pain was induced by bolus injection of hypertonic saline into m. biceps brachii, and isotonic saline was used as control. Twelve subjects performed sustained elbow flexion at different levels of the maximal voluntary contraction (5-30% MVC) before, during, and after the injections. Three-dimensional force components were measured simultaneously with surface electromyography (EMG) from elbow flexors and auxiliary muscles. Results showed that force variability was increased during pain compared to baseline for contractions using one-dimensional feedback (PEMG activity from m. trapezius was increased during contractions using both one-dimensional and three-dimensional feedback (PEMG from m. triceps brachii and m. deltoid was higher for the three-dimensional feedback (P<.05). In conclusion, the three-dimensional feedback reduced the pain-related functional distortion at the cost of a more complex control of synergistic muscles.

  2. The effects of topical Arnica on performance, pain and muscle damage after intense eccentric exercise.

    Science.gov (United States)

    Pumpa, Kate L; Fallon, Kieran E; Bensoussan, Alan; Papalia, Shona

    2014-01-01

    The aim of the study was to determine if topical Arnica is effective in reducing pain, indicators of inflammation and muscle damage, and in turn improve performance in well-trained males experiencing delayed onset muscle soreness (DOMS). Twenty well-trained males matched by maximal oxygen uptake (V̇O2 Max) completed a double-blind, randomised placebo-controlled trial. Topical Arnica was applied to the skin superficial to the quadriceps and gastrocnemius muscles immediately after a downhill running protocol designed to induce DOMS. Topical Arnica was reapplied every 4 waking hours for the duration of the study. Performance measures (peak torque, countermovement and squat jump), pain assessments (visual analogue scale (VAS) and muscle tenderness) and blood analysis (interleukin-1 beta, interleukin-6, tumour necrosis factor-alpha, C-reactive protein, myoglobin and creatine kinase) were assessed at seven time points over five days (pre-, post-, 4, 24, 48, 72 and 96 hours after the downhill run). Participants in the topical Arnica group reported less pain as assessed through muscle tenderness and VAS 72 hours post-exercise. The application of topical Arnica did not affect any performance assessments or markers of muscle damage or inflammation. Topical Arnica used immediately after intense eccentric exercise and for the following 96 hours did not have an effect on performance or blood markers. It did however demonstrate the possibility of providing pain relief three days post-eccentric exercise.

  3. EFFECTIVENESS OF MUSCLE ENERGY TECHNIQUE ON PAIN AND CERVICAL RANGE OF MOTION IN PATIENTS WITH MYOFASCIAL PAIN IN UPPER TRAPEZIUS

    Directory of Open Access Journals (Sweden)

    M. Srikanth

    2015-02-01

    Full Text Available Back ground: Myofascial trigger point (MTPt can be defined as a hyperirritable spot in skeletal muscle that is associated with a hypersensitive palpable nodule in a taut band. MTPt is associated with pain on compression, the pain is typically of a referred type. MTPt symptoms, cause severe discomfort and inability to work. The pain is aggravated with activity or stress. Untreated, chronic cases might lead to symptoms like depression, fatigue and behavioural disturbances. The objective of the study is to examine the effectiveness of MET on pain with VAS and cervical ROM with inch tape method in patients with myofascial pain in upper trapezius. Methods: participants were randomized into intervention group (n =15 and control group (n = 15.The intervention group was given muscle energy technique, ischemic compression and ultrasound. The control group was given only ischemic compression and ultrasound. Ultrasound 1 MHz continuous mode, intensity 1.5W/cm2 for 5 minutes. Home exercises taught to both the groups. This program designed for daily for 1 week. Outcome measures: Pain-VAS, ROM-Inch tape method (cervical lateral flexion. Results: values within the groups were compared by using paired `t` test. According to obtained values, the pre & posttest values of pain and ROM had an significant effect on p-values 0.00 in experimental group. The difference between the pretest and posttest scores of 95% confidence intervals for each outcome variable was reported. Conclusion: After 1 week of intervention protocol, the present study concludes that MET has significant improvement in pain, ROM in intervention group.

  4. Do Psychosocial Factors Predict Muscle Strength, Pain, or Physical Performance in Patients With Knee Osteoarthritis?

    Science.gov (United States)

    Baert, Isabel A C; Meeus, Mira; Mahmoudian, Armaghan; Luyten, Frank P; Nijs, Jo; Verschueren, Sabine M P

    2017-09-01

    The aim of this study was to examine the relationship of psychosocial factors, namely, pain catastrophizing, kinesiophobia, and maladaptive coping strategies, with muscle strength, pain, and physical performance in patients with knee osteoarthritis (OA)-related symptoms. A total of 109 women (64 with knee OA-related symptoms) with a mean age of 65.4 years (49-81 years) were recruited for this study. Psychosocial factors were quantified by the Pain Catastrophizing Scale, Tampa Scale for Kinesiophobia, and Pain Coping Inventory. Clinical features were assessed using isometric and isokinetic knee muscle strength measurements, visual analog scale, Western Ontario and McMaster Universities Osteoarthritis Index, and functional tests. Associations were examined using correlation and regression analysis. In knee OA patients, pain catastrophizing, kinesiophobia, and coping strategy explained a significant proportion of the variability in isometric knee extension and flexion strength (6.3%-9.2%), accounting for more overall variability than some demographic and medical status variables combined. Psychosocial factors were not significant independent predictors of isokinetic strength, knee pain, or physical performance. In understanding clinical features related to knee OA, such as muscle weakness, pain catastrophizing, kinesiophobia, and coping strategy might offer something additional beyond what might be explained by traditional factors, underscoring the importance of a biopsychosocial approach in knee OA management. Further research on individual patient characteristics that mediate the effects of psychosocial factors is, however, required in order to create opportunities for more targeted, personalized treatment for knee OA.

  5. Efficacy of tart cherry juice in reducing muscle pain during running: a randomized controlled trial

    Directory of Open Access Journals (Sweden)

    Elliot Diane L

    2010-05-01

    Full Text Available Abstract Background Long distance running causes acute muscle damage resulting in inflammation and decreased force production. Endurance athletes use NSAIDs during competition to prevent or reduce pain, which carries the risk of adverse effects. Tart cherries, rich in antioxidant and anti-inflammatory properties, may have a protective effect to reduce muscle damage and pain during strenuous exercise. This study aimed to assess the effects of tart cherry juice as compared to a placebo cherry drink on pain among runners in a long distance relay race. Methods The design was a randomized, double blind, placebo controlled trial. Fifty-four healthy runners (36 male, 18 female; 35.8 ± 9.6 yrs ran an average of 26.3 ± 2.5 km over a 24 hour period. Participants ingested 355 mL bottles of tart cherry juice or placebo cherry drink twice daily for 7 days prior to the event and on the day of the race. Participants assessed level of pain on a standard 100 mm Visual Analog Scale (VAS at baseline, before the race, and after the race. Results While both groups reported increased pain after the race, the cherry juice group reported a significantly smaller increase in pain (12 ± 18 mm compared to the placebo group (37 ± 20 mm (p Conclusions Ingesting tart cherry juice for 7 days prior to and during a strenuous running event can minimize post-run muscle pain.

  6. Effect of brief daily resistance training on rapid force development in painful neck and shoulder muscles

    DEFF Research Database (Denmark)

    Jay, Kenneth; Schraefel, Mc; Andersen, Christoffer H

    2013-01-01

    OBJECTIVE: To determine the effect of small daily amounts of progressive resistance training on rapid force development of painful neck/shoulder muscles. METHODS: 198 generally healthy adults with frequent neck/shoulder muscle pain (mean: age 43.1 years, computer use 93% of work time, 88% women...... performed maximal voluntary contractions at a static 90-degree shoulder joint angle. Rapid force development was determined as the rate of torque development and maximal muscle strength was determined as the peak torque. RESULTS: Compared with the control group, rate of torque development increased 31.0 Nm...... relationship existed between changes in rapid force development and pain (r = 0.27, Prapid force development and...

  7. Ultrasonic tissue characterization of the upper trapezius muscle in patients with myofascial pain syndrome.

    Science.gov (United States)

    Turo, Diego; Otto, Paul; Shah, Jay P; Heimur, Juliana; Gebreab, Tadesse; Armstrong, Katherine; Gerber, Lynn H; Sikdar, Siddhartha

    2012-01-01

    Myofascial trigger points (MTrPs) are palpable, tender nodules in skeletal muscle that produce symptomatic referred pain when palpated. MTrPs are characteristic findings in myofascial pain syndrome (MPS). The role of MTrPs in the pathophysiology of MPS is unknown. Objective characterization and quantitative measurement of the properties of MTrPs can improve their localization and diagnosis, as well as lead to clinical outcome measures. MTrPs associated with soft tissue neck pain are often found in the upper trapezius muscle. We have previously demonstrated that MTrPs can be visualized using ultrasound imaging. The goal of this study was to evaluate whether texture-based image analysis can differentiate structural heterogeneity of symptomatic MTrPs and normal muscle.

  8. Efficacy of thiocolchicoside in Indian patients suffering from low back pain associated with muscle spasm.

    Science.gov (United States)

    Soonawalla, Darius F; Joshi, Niteen

    2008-05-01

    Low back pain (LBP), a high prevalent condition among middle aged population, is usually associated with 'muscle spasm' that is responsible for giving rise to pain as well as its persistence. Muscle spasm is an involuntary, painful contraction of muscles that interferes with the function and cause of muscular disorder. Therefore centrally acting skeletal muscle relaxants, also called lissive drugs, are commonly used for its treatment. Sometimes these are combined with NSAIDs. The use of centrally acting skeletal muscle relaxants, though efficacious, is associated with frequent development of dose-related adverse drug reactions like sedation, impairment of voluntary motor functions and ataxia. So there is an urgent need for newer better drugs for treatment of conditions associated with muscle spasm. The objective of this study was to assess the efficacy and safety of oral thiocolchicoside (TC), a natural glycoside as compared to an adrenergic alpha 2 agonist tizanidine (TZ) in the Indian patients with LBP accompanied by muscle spasm. In this randomised, non-cross over clinical study, 60 adult Indians aged between 18 and 65 years with clinical diagnosis of muscle spasm associated with low back pain were enrolled. Patients satisfying the inclusion and exclusion criteria were either treated with TC and TZ for one week duration. Visual analogue scale (VAS) for pain at rest and VAS for tiredness, drowsiness, dizziness and alertness was used as the self-rated primary efficacy and safety variable. Pain was also assessed by mobility assessment; muscle spasm assessment and analgesic consumption. Data obtained from 58 patients (those who completed the study) indicated that in this one week study both TC and TZ provided sustained symptoms relief compared with the baseline. There was statistically significant reduction in severity of symptoms from day 0 to day 7 in both the groups. Patients were followed up on 3rd and 7th day and severity score of various parameters was

  9. Muscle trigger points and pressure pain hyperalgesia in the shoulder muscles in patients with unilateral shoulder impingement: a blinded, controlled study.

    Science.gov (United States)

    Hidalgo-Lozano, Amparo; Fernández-de-las-Peñas, César; Alonso-Blanco, Cristina; Ge, Hong-You; Arendt-Nielsen, Lars; Arroyo-Morales, Manuel

    2010-05-01

    Our aim was to describe the differences in the presence of trigger points (TrPs) in the shoulder muscles and to investigate the presence of mechanical hypersensitivity in patients with unilateral shoulder impingement and healthy controls. Twelve patients with strictly unilateral shoulder impingement and 10 matched controls were recruited. TrPs in the levator scapula, supraspinatus, infraspinatus, subscapularis, pectoralis major, and biceps brachii muscles were explored. TrPs were considered active if the local and referred pain reproduced the pain symptoms and the patient recognized the pain as a familiar pain. Pressure pain thresholds (PPT) were assessed over the levator scapulae, supraspinatus, infraspinatus, pectoralis major, biceps brachii, and tibialis anterior muscles. Both explorations were randomly done by an assessor blinded to the subjects' condition. Patients with shoulder impingement have a greater number of active (mean +/- SD: 2.5 +/- 1; P muscles were the most prevalent in the patient group. Patients showed a significant lower PPT in all muscles when compared to controls (P muscles were associated to greater pain intensity and lower PPTs when compared to those with latent TrPs in the same muscles (P shoulder impingement showed widespread pressure hypersensitivity and active TrPs in the shoulder muscles, which reproduce their clinical pain symptoms. Our results suggest both peripheral and central sensitisation mechanisms in patients with shoulder impingement syndrome.

  10. Restorative Effect of Vitamin D Deficiency on Knee Pain and Quadriceps Muscle Strength in Knee Osteoarthritis

    Directory of Open Access Journals (Sweden)

    Behzad Heidari

    2015-10-01

    Full Text Available Both vitamin D deficiency and quadriceps muscle weakness are associated with kneeosteoarthritis (KOA and pain. The aim of this study was to determine the restorative effect of vitamin Ddeficiency on pain and quadriceps muscle strength in knee osteoarthritis. Patients with KOA aged≥30years, the presence of knee pain for at least one month or longer and serum 25-hydroxyvitamin (25-OHDdeficiencies were recruited in the study. Participants with KOA compatible with Kellgren-Lawrence grade4, joint instability, and effusion, history of surgery or inflammatory arthropathies were excluded. Serum25-OHD was assessed by ELISA method and concentrationsQuadriceps muscle strength was measured by dynamometry method and intensity of knee pain by WesternOntario and McMaster University Osteoarthritis index scored by Likert scale and visual analog scale. Allparticipants received 50.000 IU oral cholecalciferol weekly for at least two months. The influence ofraising serum 25-OHD on quadriceps muscle strength and pain was assessed by calculation of meanchanges from baseline at the end of the treatment period using paired t-test. A total of 67 patients withmean age of 50±6.6 years of age were treated for 2 months. Serum 25-OHD reached to sufficient levels inall except one patient. At the end of the study period, serum 25-OHD and quadriceps muscle strengthincreased significantly as compared with baseline (P=0.007 and P=0.002, respectively, whereas knee paindecreased significantly based on Western Ontario and McMaster University Osteoarthritis index (P=0.001as well as visual analogue scale scores (P=0.001.These findings indicated that correction of vitamin Ddeficiency in patients with KOA exerts a significant favorable effect on quadriceps muscle strength andknee pain.

  11. EMG reactivity and oral habits among facial pain patients in a scheduled-waiting competitive task.

    Science.gov (United States)

    Nicholson, R A; Lakatos, C A; Gramling, S E

    1999-12-01

    For individuals with temporomandibular disorder (TMD) it has been theorized that stressful events trigger oral habits (e.g., teeth grinding), thereby increasing masticatory muscle tension and subsequent pain. Recent research involving adjunctive behaviors found an increase in masseter surface EMG (sEMG) and oral habits when students with TMD symptomatology were placed on a fixed-time reinforcement schedule. The current study used a treatment-seeking community sample with TMD symptomatology in a competitive task designed to be a more naturalistic Fixed Time task. The experiment consisted of Adaptation, Free-Play, Scheduled-Play, and Recovery phases. During the Scheduled-Play phase participants played, and waited to play, an electronic poker game. Results indicated that masseter muscle tension in the Scheduled-Play phase was significantly higher (p oral habits and overall affect were significantly higher (p's oral habits may lead to TMD symptomatology.

  12. Pain and soreness associated with a percutaneous electrical stimulation muscle cramping protocol.

    Science.gov (United States)

    Miller, Kevin C; Knight, Kenneth L

    2007-11-01

    Muscle cramps are difficult to study scientifically because of their spontaneity and unpredictability. Various laboratory techniques to induce muscle cramps have been explored but the best technique for inducing cramps is unclear. Electrical stimulation appears to be the most reliable, but there is a perception that it is extremely painful. Data to support this perception are lacking. We hypothesized that electrical stimulation is a tolerable method of inducing cramps with few side effects. We measured cramp frequency (HZ), pain during electrical stimulation, and soreness before, at 5 s, and 30, 60, and 90 min after cramp induction using a 100-mm visual analog scale. Group 1 received tibial nerve stimulation on 5 consecutive days; Group 2 received it on alternate days for five total treatments. Pain and soreness were mild. The highest ratings occurred on Day 1 and decreased thereafter. Intersession reliability was high. Our study showed that electrical stimulation causes little pain or soreness and is a reliable method for inducing cramps.

  13. Elevated muscle interstitial levels of pain-inducing substances in symptomatic muscles in patients with polymyalgia rheumatica

    DEFF Research Database (Denmark)

    Kreiner, Frederik; Galbo, Henrik

    2011-01-01

    with newly diagnosed PMR and 20 controls were examined before and after 14days of prednisolone (20mg/day). Concentrations of glutamate, prostaglandin E(2) (PGE(2)), bradykinin, serotonin, adenosine triphosphate, lactate, pyruvate, and potassium as well as extraction of (3)H(2)O were measured in symptomatic...... vastus lateralis and trapezius muscles using microdialysis. Plasma levels were measured simultaneously. To be considered potentially pain inducing, interstitial concentrations of candidates should be higher in patients vs. controls, be normalized by prednisolone, and be higher in muscle vs. plasma...

  14. Impaired muscle function in women with fibromyalgia is not due to pain.

    OpenAIRE

    Forsbakk, Camilla Swan

    2010-01-01

    Background: Fibromyalgia syndrome (FM) is associated with widespread pain over the entire body. Moreover, an impaired muscle function is frequently reported in FM patients. Several causes are supposed to cause these impairments, and causes can be multiply. However, the results are inconclusive.Objective: To investigate why women with FM have an impaired muscle function.Material and methods: Fifty women in the age 35-65 participated in an intervention study existing of 12 weeks indoor cycling....

  15. Lower facial remodeling with botulinum toxin type A for the treatment of masseter hypertrophy*

    Science.gov (United States)

    Klein, Fernanda Homem de Mello de Souza; Brenner, Fabiane Mulinari; Sato, Maurício Shigeru; Robert, Fernanda Manfron Batista Rosas; Helmer, Karin Adriane

    2014-01-01

    BACKGROUND Masseter hypertrophy has been treated with botulinum toxin injections because of esthetic complaints especially in Asians. OBJECTIVES The goal of the present study was to evaluate the efficacy of abobotulin toxin use in masseter hipertrophy treatment in Brazilians. METHODS Ten Brazilian female patients with masseter hypertrophy were subjected to injections of 90U of abobotulinum toxin A applied on each side respecting the safety zone stabilished in literature and were followed up for 24 weeks. RESULTS When analyzing the coefficients between measures of middle and lower third of the face obtained from standardized photographs, an increase was observed, with statistical significance at 2 weeks (p=0.005) and 12 weeks (p=0.001). The progression of lower third reduction was 3.94%, 5.26%, 11.99%, and 5.47% (2, 4, 12, and 24 weeks respectively). All patients showed improvement in bruxism after treatment. Observed adverse effects were masticatory fatigue, smile limitation, and smile asymmetry. CONCLUSION The use of abobotulinum toxin A for masseter hypertrophy is effective in Brazilians and reached its maximum effect of facial thinning at 12 weeks. Smile limitation had a higher incidence compared to that reported in the literature and may result from risorius muscle blockage caused by toxin dissemination. Despite its side effects, 80% of the patients would like to repeat the treatment. PMID:25387491

  16. A Comparison of the Deep Cervical Flexor Muscle Thicknesses in Subjects with and without Neck Pain during Craniocervical Flexion Exercises.

    Science.gov (United States)

    Jun, Ilsub; Kim, Kyoung

    2013-11-01

    [Purpose] The purpose of the present study was to examine the amount of change in the thicknesses of the deep cervical flexor (DCF) and sternocleidomastoid (SCM) muscles in subjects with neck pain and subjects without neck pain during craniocervical flexion exercise (CCFE). [Subjects] The total number of subjects was 40, comprising 20 in the no-pain group (males 11, females 9) and 20 in the pain group (males 8, females 12). [Methods] Muscle images were obtained using ultrasound, and the thicknesses of the individual muscles were measured using the NIH ImageJ software. [Results] During CCFE, as pressure increased, the no-pain group recruited the DCF more than the pain group, while the pain group recruited the SCM more. [Conclusion] Selective DCF contraction exercises are considered very useful in the treatment of patients with neck pain.

  17. Clinimetric evaluation of methods to measure muscle functioning in patients with non-specific neck pain: a systematic review.

    NARCIS (Netherlands)

    Koning, C.H. de; Heuvel, SP van den; Staal, J.B.; Smits-Engelsman, B.C.M.; Hendriks, E.J.M.

    2008-01-01

    BACKGROUND: Neck pain is a significant health problem in modern society. There is evidence to suggest that neck muscle strength is reduced in patients with neck pain. This article provides a critical analysis of the research literature on the clinimetric properties of tests to measure neck muscle st

  18. Biopsychosocial Influence on Exercise-induced Delayed Onset Muscle Soreness at the Shoulder: Pain Catastrophizing and Catechol-O-Methyltransferase (COMT) Diplotype Predict Pain Ratings

    Science.gov (United States)

    George, Steven Z.; Dover, Geoffrey C.; Wallace, Margaret R.; Sack, Brandon K.; Herbstman, Deborah M.; Aydog, Ece; Fillingim, Roger B.

    2009-01-01

    Objective The experience of pain is believed to be influenced by psychologic and genetic factors. A previous study suggested pain catastrophizing and catechol-O-methyltransferase (COMT) genotype influenced clinical pain ratings for patients seeking operative treatment of shoulder pain. This study investigated whether these same psychologic and genetic factors predicted responses to induced shoulder pain. Methods Participants (n=63) completed self-report questionnaires and had COMT genotype determined before performing a standardized fatigue protocol to induce delayed onset muscle soreness. Then, shoulder pain ratings, self-report of upper-extremity disability ratings, and muscle torque production were reassessed 24, 48, and 72 hours later. Results This cohort consisted of 35 women and 28 men, with a mean age of 20.9 years (SD=1.7). The frequency of COMT diplotypes was 42 with “high COMT enzyme activity” (low pain sensitivity group) and 21 with “low COMT enzyme activity” (average pain sensitivity/high pain sensitivity group). A hierarchical regression model indicated that an interaction between pain catastrophizing and COMT diplotype was the strongest unique predictor of 72-hour pain ratings. The same interaction was not predictive of self-report of disability or muscle torque production at 72 hours. The pain catastrophizing × COMT diplotype interaction indicated that participants with high pain catastrophizing and low COMT enzyme activity (average pain sensitivity/high pain sensitivity group) were more likely (relative risk=3.5, P=0.025) to have elevated pain intensity ratings (40/100 or higher). Discussion These findings from an experimental model converge with those from a surgical cohort and provide additional evidence that the presence of elevated pain catastrophizing and COMT diplotype indicative of low COMT enzyme activity have the potential to increase the risk of developing chronic pain syndromes. PMID:18936597

  19. The role of tooth-grinding in the maintenance of myofascial face pain: a test of alternate models.

    Science.gov (United States)

    Janal, Malvin N; Raphael, Karen G; Klausner, Jack; Teaford, Mark

    2007-09-01

    While mechanisms of myofascial face pain are poorly understood, bruxism has been implicated in the maintenance of this painful disorder. This study evaluates whether evidence of one aspect of bruxism, tooth-grinding, is positively associated with pain severity, as predicted by a psychophysiological model, or negatively associated, as predicted by an adaptation model of face pain. Participants were 51 women who met Research Diagnostic Criteria for the myofascial subtype of temporomandibular disorder. Tooth-grinding was quantified by changes in microwear features of the molar teeth over 2 weeks. Palpated pain severity was quantified on an 11-point scale in response to palpation of the skin overlying the masseter and temporalis muscles bilaterally. Other measures included validated scales of spontaneous pain severity, stress, distress, and psychological symptoms. Association was quantified as Pearson correlation coefficients. Data showed an inverse correlation (r = -0.37, P pain severity and the index of tooth wear, supporting the adaptation model. This correlation provided a weighted average of a strong effect (r = -0.80, P pain only the right side of their face with an effect that approximated zero in those reporting bilateral pain. Tooth wear measures were negatively associated with ratings of pain severity only over the right masseter. While these data do not address the role of clenching, they cast serious doubt on the theory that myofascial face pain is maintained by tooth-grinding.

  20. The Associations between Pain Sensitivity and Knee Muscle Strength in Healthy Volunteers: A Cross-Sectional Study

    Directory of Open Access Journals (Sweden)

    Marius Henriksen

    2013-01-01

    Full Text Available Objectives. To investigate associations between muscle strength and pain sensitivity among healthy volunteers and associations between different pain sensitivity measures. Methods. Twenty-eight healthy volunteers (21 females participated. Pressure pain thresholds (PPTs were obtained from 1 computer-controlled pressure algometry on the vastus lateralis and deltoid muscles and on the infrapatellar fat pad and 2 computerized cuff pressure algometry applied on the lower leg. Deep-tissue pain sensitivity (intensity and duration was assessed by hypertonic saline injections into the vastus lateralis, deltoid, and infrapatellar fat pad. Quadriceps and hamstring muscle strength was assessed isometrically at 60-degree knee flexion using a dynamometer. Associations between pain sensitivity and muscle strength were investigated using multiple regressions including age, gender, and body mass index as covariates. Results. Knee extension strength was associated with computer-controlled PPT on the vastus lateralis muscle. Computer-controlled PPTs were significantly correlated between sites (r>0.72 and with cuff PPT (r>0.4. Saline induced pain intensity and duration were correlated between sites (r>0.39 and with all PPTs (r<-0.41. Conclusions. Pressure pain thresholds at the vastus lateralis are positively associated with knee extensor muscle strength. Different pain sensitivity assessment methods are generally correlated. The cuff PPT and evoked infrapatellar pain seem to reflect the general pain sensitivity. This trial is registered with ClinicalTrials.gov: NCT01351558.

  1. Characterization of the Muscle Electrical Properties in Low Back Pain Patients by Electrical Impedance Myography

    OpenAIRE

    Congo Tak-Shing Ching; Yueh-Chi Chen; Li-Hua Lu; Hsieh, Peiyuan F; Chin-Sung Hsiao; Tai-Ping Sun; Hsiu-Li Shieh; Kang-Ming Chang

    2013-01-01

    OBJECTIVES: This study aims to investigate the electrical properties of lumbar paraspinal muscles (LPM) of patients with acute lower back pain (LBP) and to study a new approach, namely Electrical Impedance Myography (EIM), for reliable, low-cost, non-invasive, and real-time assessment of muscle-strained acute LBP. DESIGN: Patients with muscle-strained acute LBP (n = 30) are compared to a healthy reference group (n = 30). Electrical properties of LPM are studied. BACKGROUND: EIM is a novel tec...

  2. High prevalence of shoulder girdle muscles with myofascial trigger points in patients with shoulder pain

    Science.gov (United States)

    2011-01-01

    Background Shoulder pain is reported to be highly prevalent and tends to be recurrent or persistent despite medical treatment. The pathophysiological mechanisms of shoulder pain are poorly understood. Furthermore, there is little evidence supporting the effectiveness of current treatment protocols. Although myofascial trigger points (MTrPs) are rarely mentioned in relation to shoulder pain, they may present an alternative underlying mechanism, which would provide new treatment targets through MTrP inactivation. While previous research has demonstrated that trained physiotherapists can reliably identify MTrPs in patients with shoulder pain, the percentage of patients who actually have MTrPs remains unclear. The aim of this observational study was to assess the prevalence of muscles with MTrPs and the association between MTrPs and the severity of pain and functioning in patients with chronic non-traumatic unilateral shoulder pain. Methods An observational study was conducted. Subjects were recruited from patients participating in a controlled trial studying the effectiveness of physical therapy on patients with unilateral non-traumatic shoulder pain. Sociodemographic and patient-reported symptom scores, including the Disabilities of the Arm, Shoulder, and Hand (DASH) Questionnaire, and Visual Analogue Scales for Pain were compared with other studies. To test for differences in age, gender distribution, and education level between the current study population and the populations from Dutch shoulder studies, the one sample T-test was used. One observer examined all subjects (n = 72) for the presence of MTrPs. Frequency distributions, means, medians, standard deviations, and 95% confidence intervals were calculated for descriptive purposes. The Spearman's rank-order correlation (ρ) was used to test for association between variables. Results MTrPs were identified in all subjects. The median number of muscles with MTrPs per subject was 6 (active MTrPs) and 4 (latent MTr

  3. High prevalence of shoulder girdle muscles with myofascial trigger points in patients with shoulder pain

    Directory of Open Access Journals (Sweden)

    Wensing Michel

    2011-06-01

    Full Text Available Abstract Background Shoulder pain is reported to be highly prevalent and tends to be recurrent or persistent despite medical treatment. The pathophysiological mechanisms of shoulder pain are poorly understood. Furthermore, there is little evidence supporting the effectiveness of current treatment protocols. Although myofascial trigger points (MTrPs are rarely mentioned in relation to shoulder pain, they may present an alternative underlying mechanism, which would provide new treatment targets through MTrP inactivation. While previous research has demonstrated that trained physiotherapists can reliably identify MTrPs in patients with shoulder pain, the percentage of patients who actually have MTrPs remains unclear. The aim of this observational study was to assess the prevalence of muscles with MTrPs and the association between MTrPs and the severity of pain and functioning in patients with chronic non-traumatic unilateral shoulder pain. Methods An observational study was conducted. Subjects were recruited from patients participating in a controlled trial studying the effectiveness of physical therapy on patients with unilateral non-traumatic shoulder pain. Sociodemographic and patient-reported symptom scores, including the Disabilities of the Arm, Shoulder, and Hand (DASH Questionnaire, and Visual Analogue Scales for Pain were compared with other studies. To test for differences in age, gender distribution, and education level between the current study population and the populations from Dutch shoulder studies, the one sample T-test was used. One observer examined all subjects (n = 72 for the presence of MTrPs. Frequency distributions, means, medians, standard deviations, and 95% confidence intervals were calculated for descriptive purposes. The Spearman's rank-order correlation (ρ was used to test for association between variables. Results MTrPs were identified in all subjects. The median number of muscles with MTrPs per subject was 6 (active

  4. Elite swimmers with and without unilateral shoulder pain: mechanical hyperalgesia and active/latent muscle trigger points in neck-shoulder muscles.

    Science.gov (United States)

    Hidalgo-Lozano, A; Fernández-de-las-Peñas, C; Calderón-Soto, C; Domingo-Camara, A; Madeleine, P; Arroyo-Morales, M

    2013-02-01

    Our aim was to investigate the presence of mechanical hypersensitivity and active trigger points (TrPs) in the neck-shoulder muscles in elite swimmers with/without unilateral shoulder pain. Seventeen elite swimmers with shoulder pain; 18 swimmers without shoulder pain; and 15 elite athletes matched controls were recruited. Pressure pain thresholds (PPT) were assessed over the levator scapulae, sternocleidomastoid, upper trapezius, infraspinatus, scalene, subscapularis and tibialis anterior muscles. TrPs in the levator scapulae, upper trapezius, infraspinatus, scalene, sternocleidomastoid and subscapularis muscles were also explored. Swimmers with shoulder pain showed significant lower PPT in all muscles compared with controls (Ppain, underlining widespread mechanical hypersensitivity. The mean number of TrPs for elite swimmer with and without shoulder pain was, respectively, 4.7 ± 1 (2.1 ± 1.5 active; 2.6 ± 1.4 latent) and 4.7 ± 1.3 (1.3 ± 1.3 active; 3.4 ± 1.5 latent), whereas healthy athletes only showed latent TrPs (2.4 ± 1.2). Elite swimmers with shoulder pain showed higher number of active TrPs than swimmers without pain, whereas it was the opposite for the number of latent muscle TrP (Pmechanical hypersensitivity suggests that active TrPs play a role in the development of shoulder pain in elite swimmers.

  5. Chronic pelvic pain arising from dysfunctional stabilizing muscles of the hip joint and pelvis.

    Science.gov (United States)

    Lee, Dae Wook; Lim, Chang Hun; Han, Jae Young; Kim, Woong Mo

    2016-10-01

    Chronic pelvic pain in women is a very annoying condition that is responsible for substantial suffering and medical expense. But dealing with this pain can be tough, because there are numerous possible causes for the pelvic pain such as urologic, gynecologic, gastrointestinal, neurologic, or musculoskeletal problems. Of these, musculoskeletal problem may be a primary cause of chronic pelvic pain in patients with a preceding trauma to the low back, pelvis, or lower extremities. Here, we report the case of a 54-year-old female patient with severe chronic pelvic pain after a transcutaneous electrical nerve stimulation (TENS) accident that was successfully managed with image-guided trigger point injections on several pelvic stabilizing muscles.

  6. Effects of experimental muscle pain on force variability during task-related and three directional isometric force task

    DEFF Research Database (Denmark)

    Mista, Christian Ariel; Graven-Nielsen, Thomas

    2013-01-01

    injected into the biceps brachii muscle. The coefficient of variation (CV) was used to analyze the variability on the task-related force direction. The total excursion of the center of pressure (CoP) was used to quantify the variability on the tangential force directions. Complexity of the force......Experimentally muscle pain induces changes in the distribution of muscle activity and affects the muscle coordination. The force steadiness is impaired during muscle pain in the task-related force direction as well as in the tangential directions. In addition, pain lead to a mismatch between......-dimensional force task during acute muscle pain. Twelve right-handed healthy volunteers participated in the experiment. Three-dimensional force signals were acquired during isometric elbow flexion at 5%, 15%, and 30% of the maximum voluntary contraction (MVC). The force components were represented by a circle...

  7. EFFECT OF KINESIO TAPING VERSUS ATHLETIC TAPING ON PAIN AND MUSCLE PERFORMANCE IN LATERAL EPICONDYLALGIA

    Directory of Open Access Journals (Sweden)

    Rashi Goel

    2015-02-01

    Full Text Available Lateral epicondylalgia is a degenerative musculoskeletal pain state characterised by pain over the lateral humeral epicondyle resulting in absenteeism from work and daily living activities. It is most prevalent in jobs requiring repetitive manual activities of the upper extremity. Literature describes different treatment options for lateral Epicondylalgia but there is no consensus about the most efficacious intervention strategy. Taping (athletic/kinesio has been used successfully in various musculoskeletal conditions with successful results. To date, no study has investigated the effect of kinesio taping in lateral epicondylalgia. The purpose of the study was to investigate and compare the effects of kinesio taping and athletic taping on pain and muscle performance in patients with lateral epicondylalgia. 16 patients (9 males, 7 females within age group of 18 – 50 years participated in the study. It was a cross over design. VAS, digital al goniometer and Jamar Dynamometer were used to quantify pain, pressure pain threshold and pain free grip strength. These were evaluated pre taping, immediately after taping and after 30 minutes of each taping application selected randomly for two consecutive days. Repeated measures ANOVA and percentage change were used to examine differences in outcome measures. Bonferroni correction was applied to correct for repeated testing. The results showed significant pain reduction and increase in grip strength after both the taping techniques but no statistically significant differences for any outcome measure between the two taping techniques (p>0.05. Also the immediate pain reduction was more after athletic taping (21% than kinesio taping (10% that corresponded to the immediate increase in pain free grip strength more after athletic taping (14.5% than kinesio taping (9.7%. 30 minutes later both the outcome measures gave similar percentage changes . The present study concludes with the recommendation of both

  8. Influence of shoulder pain on muscle function: implications for the assessment and therapy of shoulder disorders.

    Science.gov (United States)

    Struyf, Filip; Lluch, Enrique; Falla, Deborah; Meeus, Mira; Noten, Suzie; Nijs, Jo

    2015-02-01

    Shoulder pain is often a challenging clinical phenomenon because of the potential mismatch between pathology and the perception of pain. Current evidence clearly emphasizes an incomplete understanding of the nature of shoulder pain. Indeed, the effective diagnosis and treatment of shoulder pain should not only rely upon a detailed knowledge of the peripheral pathologies that may be present in the shoulder, but also on current knowledge of pain neurophysiology. To assess and treat shoulder pain, a comprehensive understanding of the way in which pain is processed is essential. This review reflects modern pain neurophysiology to the shoulder and aims to answer the following questions: why does my shoulder hurt? What is the impact of shoulder pain on muscle function? What are the implications for the clinical examination of the shoulder? And finally, what are the clinical implications for therapy? Despite the increasing amount of research in this area, an in-depth understanding of the bidirectional nociception-motor interaction is still far from being achieved. Many questions remain, especially related to the treatment of nociception-motor interactions.

  9. Pelvic floor muscle dysfunctions are prevalent in female chronic pelvic pain

    DEFF Research Database (Denmark)

    Loving, S; Thomsen, Thordis; Jaszczak, Poul P.

    2014-01-01

    BACKGROUND: No current standardized set of pelvic floor muscle (PFM) outcome measures have been specifically tested for their applicability in a general female chronic pelvic pain (CPP) population. We aimed to compare PFM function between a randomly selected population-based sample of women...

  10. Clinimetric evaluation of methods to measure muscle functioning in patients with non-specific neck pain: a systematic review

    OpenAIRE

    2008-01-01

    Abstract Background Neck pain is a significant health problem in modern society. There is evidence to suggest that neck muscle strength is reduced in patients with neck pain. This article provides a critical analysis of the research literature on the clinimetric properties of tests to measure neck muscle strength or endurance in patients with non-specific neck pain, which can be used in daily practice. Methods A computerised literature search was performed in the Medline, CINAHL and Embase da...

  11. Central projection of pain arising from delayed onset muscle soreness (DOMS in human subjects.

    Directory of Open Access Journals (Sweden)

    Katharina Zimmermann

    Full Text Available Delayed onset muscle soreness (DOMS is a subacute pain state arising 24-48 hours after a bout of unaccustomed eccentric muscle contractions. Functional magnetic resonance imaging (fMRI was used to examine the patterns of cortical activation arising during DOMS-related pain in the quadriceps muscle of healthy volunteers evoked by either voluntary contraction or physical stimulation. The painful movement or physical stimulation of the DOMS-affected thigh disclosed widespread activation in the primary somatosensory and motor (S1, M1 cortices, stretching far beyond the corresponding areas somatotopically related to contraction or physical stimulation of the thigh; activation also included a large area within the cingulate cortex encompassing posteroanterior regions and the cingulate motor area. Pain-related activations were also found in premotor (M2 areas, bilateral in the insular cortex and the thalamic nuclei. In contrast, movement of a DOMS-affected limb led also to activation in the ipsilateral anterior cerebellum, while DOMS-related pain evoked by physical stimulation devoid of limb movement did not.

  12. Effects of therapeutic massage on gait and pain after delayed onset muscle soreness.

    Science.gov (United States)

    Han, Jun-Ho; Kim, Min-Jeong; Yang, Hyuk-Jin; Lee, Yu-Jin; Sung, Yun-Hee

    2014-04-01

    Unfamiliar or sudden exercise can induce delayed onset muscle soreness (DOMS) within 12-24 h. So, several researchers have reported various interventions to treat DOMS. Massage is generally known to eliminate muscle fatigue. However, effect of massage after DOMS is still not clear. We investigated whether the massage is effective on pain and gait after DOMS. The participants were divided into a control group (n= 10) with DOMS and an experimental group (n= 11) with the massage treated after DOMS. We induced DOMS by taking isotonic exercise with going up and down 20 times in 5-story building. We applied the massage and assessment on gastrocnemius of dominant foot. The change of gait and pain was assessed using gaitrite and algometer. In the present results, the massage on gastrocnemius after DOMS showed significant difference in pain (P< 0.05). Also, there was a significant difference in gait (P< 0.05), especially, spatial parameters (distance, step length, stride length) and temporal parameters (ambulation, heel on off time, stride velocity). Moreover, the pain relief after massage-treated in DOMS correlated with gait. These results suggest that the massage on gastrocnemius after DOMS has influence on pain and gait performance. Therefore, massage can be applied as intervention for delayed onset muscle soreness.

  13. Central Projection of Pain Arising from Delayed Onset Muscle Soreness (DOMS) in Human Subjects

    Science.gov (United States)

    Zimmermann, Katharina; Leidl, Caroline; Kaschka, Miriam; Carr, Richard W.; Terekhin, Pavel; Handwerker, Hermann O.; Forster, Clemens

    2012-01-01

    Delayed onset muscle soreness (DOMS) is a subacute pain state arising 24–48 hours after a bout of unaccustomed eccentric muscle contractions. Functional magnetic resonance imaging (fMRI) was used to examine the patterns of cortical activation arising during DOMS-related pain in the quadriceps muscle of healthy volunteers evoked by either voluntary contraction or physical stimulation. The painful movement or physical stimulation of the DOMS-affected thigh disclosed widespread activation in the primary somatosensory and motor (S1, M1) cortices, stretching far beyond the corresponding areas somatotopically related to contraction or physical stimulation of the thigh; activation also included a large area within the cingulate cortex encompassing posteroanterior regions and the cingulate motor area. Pain-related activations were also found in premotor (M2) areas, bilateral in the insular cortex and the thalamic nuclei. In contrast, movement of a DOMS-affected limb led also to activation in the ipsilateral anterior cerebellum, while DOMS-related pain evoked by physical stimulation devoid of limb movement did not. PMID:23056613

  14. An oblique muscle hematoma as a rare cause of severe abdominal pain: a case report

    Directory of Open Access Journals (Sweden)

    Shimodaira Masanori

    2013-01-01

    Full Text Available Abstract Background Abdominal wall hematomas are an uncommon cause of acute abdominal pain and are often misdiagnosed. They are more common in elderly individuals, particularly in those under anticoagulant therapy. Most abdominal wall hematomas occur in the rectus sheath, and hematomas within the oblique muscle are very rare and are poorly described in the literature. Here we report the case of an oblique muscle hematoma in a middle-aged patient who was not under anticoagulant therapy. Case presentation A 42-year-old Japanese man presented with a painful, enlarging, lateral abdominal wall mass, which appeared after playing baseball. Abdominal computed tomography and ultrasonography showed a large soft tissue mass located in the patient’s left internal oblique muscle. A diagnosis of a lateral oblique muscle hematoma was made and the patient was treated conservatively. Conclusion Physicians should consider an oblique muscle hematoma during the initial differential diagnosis of pain in the lateral abdominal wall even in the absence of anticoagulant therapy or trauma.

  15. Modulation of trigeminal laser evoked potentials and laser silent periods by homotopical experimental pain.

    Science.gov (United States)

    Romaniello, Antonietta; Arendt-Nielsen, Lars; Cruccu, Giorgio; Svensson, Peter

    2002-07-01

    Cutaneous laser stimulation activates predominantly the A-delta and C mechano-heat nociceptors. Applied to the perioral region, low intensity CO(2)-laser pulses evoke reproducible trigeminal cortical evoked potentials (LEPs). High intensity CO(2)-laser stimuli induce a reflex response in the contracted jaw-closing muscle, the so-called laser silent period (LSP). Both LEPs and LSP provide a useful tool to study the physiology of the trigeminal nociceptive system. In ten healthy subjects we recorded the subjective ratings of the perioral laser stimulation and the trigeminal LEPs and LSP before, during and after homotopic experimental tonic muscle (infusion of hypertonic saline into the masseter muscle) and tonic skin pain (topical application of capsaicin to the cheek). LEPs were recorded from the vertex at two stimulus intensities: low (1.1 x pain threshold, PTh) and high (1.5 x PTh). LSP from masseter and temporalis muscles were recorded bilaterally through surface electromyographic (EMG) electrodes. CO(2)-laser pulses were applied to the perioral region (V2/V3) on the painful and non-painful side. The amplitude of LEPs increased with higher stimulus intensities (P 0.20). The LSP in the masseter and temporalis muscles had similar onset-latency (80+/-5 ms), offset-latency (111+/-5 ms) and duration (31+/-4 ms). Experimental pain had no effect on the onset- and offset-latency (P>0.05). Experimental pain, whether from muscle or from skin, reduced the degree of suppression (PEMG curve (P< 0.005) of the LSP. The LSP was still suppressed during the post-pain recordings when the skin pain had disappeared (P<0.05). In all experiments experimental tonic pain decreased the subjective ratings of the perioral laser stimulation (P< 0.001). Experimental tonic pain, either from muscle or from skin, induced bilateral inhibitory effects on the trigeminal laser evoked potentials and brainstem reflex responses and on the subjective ratings of the laser pulses. These effects could be

  16. Effect of cycling on oxygenation of relaxed neck/shoulder muscles in women with and without chronic pain

    DEFF Research Database (Denmark)

    Andersen, Lars L; Blangsted, Anne Katrine; Nielsen, Pernille Kofoed

    2010-01-01

    Work-related neck/shoulder muscle pain has been associated with increased anaerobic muscle metabolism. Thus, interventions to enhance oxygenation of painful muscles seem relevant. While cycling with relaxed shoulders has been shown to result in acute neck/shoulder muscle pain reduction, the effect......-maximal cycling in an upright position with relaxed shoulders. Near-infrared spectroscopy was used to measure trapezius muscle oxygenation during and 2 min after the cycling period. For both MYA and CON, oxygenation of the passive trapezius increased in a linear fashion over time, to values approximately 5 micro...... increases oxygenation of resting neck/shoulder muscles in women with and without trapezius myalgia, indicating acute positive effects of either neural or humoral factors on vascular beds of distant relaxed muscles. Although this beneficial response was observed in both groups, the post-exercise response...

  17. The intra- and inter-rater reliability of five clinical muscle performance tests in patients with and without neck pain

    DEFF Research Database (Denmark)

    Sørensen, Tina Juul; Langberg, Henning; Enoch, Flemming;

    2013-01-01

    trials are often performed. However, when muscle performance tests are applied in the clinical setting, clinicians often only conduct a muscle performance test once as repeated testing may produce fatigue and pain, thus variation in test results. We aimed to investigate whether cervical muscle...

  18. Unusual fatal petrositis presenting as myofascial pain and dysfunction of the temporal muscle.

    Science.gov (United States)

    Loretan, Stefan; Duvoisin, Bernard; Scolozzi, Paolo

    2011-05-01

    Petrositis is a rare and severe complication of acute otitis media and mastoiditis. Although the extension of the inflammatory process from the petrous apex to the adjacent Meckel cave can lead to trigeminal pain, an irritation of the trigeminal nerve roots resulting in acute or chronic hyperactivity of masticatory muscles has never been reported. We report here the unusual case of an 86-year-old man who presented with a handicapping myofascial pain and dysfunction syndrome of the right temporal muscle as a heralding manifestation of an unusual form of petrositis. The patient progressively developed a retropharyngeal abscess, a right sphenoid sinusitis, and fatal meningitis. This case demonstrated that (1) myofascial pain and dysfunction syndrome that does not respond to conventional treatments may suggest an unusual etiology and warrant further medical investigations and a detailed medical history and that (2) petrositis can manifest itself with atypical clinical symptoms and radiologic signs.

  19. Changes in muscle activity determine progression of clinical symptoms in patients with chronic spine-related muscle pain. A complex clinical and neurophysiological approach.

    Science.gov (United States)

    Wytrazek, Marcin; Huber, Juliusz; Lisinski, Przemyslaw

    2011-01-01

    Spine-related muscle pain can affect muscle strength and motor unit activity. This study was undertaken to investigate whether surface electromyographic (sEMG) recordings performed during relaxation and maximal contraction reveal differences in the activity of muscles with or without trigger points (TRPs). We also analyzed the possible coexistence of characteristic spontaneous activity in needle electromyographic (eEMG) recordings with the presence of TRPs. Thirty patients with non-specific cervical and back pain were evaluated using clinical, neuroimaging and electroneurographic examinations. Muscle pain was measured using a visual analog scale (VAS), and strength using Lovett's scale; trigger points were detected by palpation. EMG was used to examine motor unit activity. Trigger points were found mainly in the trapezius muscles in thirteen patients. Their presence was accompanied by increased pain intensity, decreased muscle strength, increased resting sEMG amplitude, and decreased sEMG amplitude during muscle contraction. eEMG revealed characteristic asynchronous discharges in TRPs. The results of EMG examinations point to a complexity of muscle pain that depends on progression of the myofascial syndrome.

  20. AN ELECTROMYOGRAPHIC STUDY OF WHETHER THE DIGASTRIC MUSCLES ARE CONTROLLED BY JAW-CLOSING PROPRIOCEPTORS IN MAN

    NARCIS (Netherlands)

    VANWILLIGEN, JD; MORIMOTO, T; BROEKHUIJSEN, ML; BIJL, GK; INOUE, T

    1993-01-01

    Whether in the oral system the digastric muscles (which lack muscle spindles) are under the control of proprioceptive information from the masseter muscles (which contain muscle spindles) was investigated by analysing whether and how the masseters and digastrics showed coordinated behaviour during a

  1. Referred pain elicited by manual exploration of the lateral rectus muscle in chronic tension-type headache.

    Science.gov (United States)

    Fernández-de-Las-Peñas, César; Cuadrado, Maria Luz; Gerwin, Robert D; Pareja, Juan A

    2009-01-01

    To analyze the presence of referred pain elicited by manual examination of the lateral rectus muscle in patients with chronic tension-type headache (CTTH). A case-control blinded study. It has been found previously that the manual examination of the superior oblique muscle can elicit referred pain to the head in some patients with migraine or tension-type headache. However, a referred pain from other extraocular muscles has not been investigated. Fifteen patients with CTTH and 15 healthy subjects without headache history were included. A blinded assessor performed a manual examination focused on the search for myofascial trigger points (TrPs) in the right and left lateral rectus muscles. TrP diagnosis was made when there was referred pain evoked by maintained pressure on the lateral corner of the orbit (anatomical projection of the lateral rectus muscle) for 20 seconds, and increased referred pain while the subject maintained a medial gaze on the corresponding side (active stretching of the muscle) for 15 seconds. On each side, a 10-point numerical pain rate scale was used to assess the intensity of referred pain at both stages of the examination. Ten patients with CTTH (66.6%) had referred pain that satisfied TrPs diagnostic criteria, while only one healthy control (0.07%) reported referred pain upon the examination of the lateral rectus muscles (P < 0.001). The elicited referred pain was perceived as a deep ache located at the supraorbital region or the homolateral forehead. Pain was evoked on both sides in all subjects with TrPs, with no difference in pain intensity between the right and the left. The average pain intensity was significantly greater in the patient group (P < 0.001). All CTTH patients with referred pain recognized it as the frontal pain that they usually experienced during their headache attacks, which was consistent with active TrPs. In some patients with CTTH, the manual examination of lateral rectus muscle TrPs elicits a referred pain that

  2. Effect of Quadriceps Exercise Training on Muscle Fiber Angle in Patients With Patellofemoral Pain Syndrome

    Directory of Open Access Journals (Sweden)

    Honarpishe

    2015-10-01

    Full Text Available Background Imbalance between the vastus medialis oblique (VMO muscle and the vastus lateralis oblique (VTO Vastus lateralis has been thought to be a primary cause of abnormal patellar tracking, possibly leading to patellofemoral pain syndrome (PFPS. Objectives The purpose of this study was to investigate the effect of quadriceps muscle strengthening exercises on the ratio of VMO to VL oblique and longus muscle fiber angles. Patients and Methods Thirty-five subjects (23 females and 12 males, mean age 26.6 years ± 1.1 SD with PFPS were randomized into an exercise group or a control group. The exercise group performed knee extension exercises for four weeks based on the Kaya exercise program (three times per week, while the control group received no treatment. Measurements included knee extensor concentric and eccentric muscle torque using a Biodex isokinetic machine and the fiber angle of the VMO, VL oblique and longus muscles using ultrasonography, all of which were evaluated at the time of the initial examination and at the end of the four-week period. Results There were no significant differences in the muscle strength and fiber angle of the VMO, VL oblique and longus muscles after training between the control and experimental groups (P > 0.05. Conclusions The study findings indicate that short-term exercises had no significant effect on the ratio of VMO to VL muscle fiber angles in patients with PFPS.

  3. Ultrasonographic analysis of dorsal neck muscles thickness changes induced by isometric contraction of shoulder muscles: A comparison between patients with chronic neck pain and healthy controls.

    Science.gov (United States)

    Karimi, Noureddin; Rezasoltani, Asghar; Rahnama, Leila; Noori-Kochi, Farhang; Jaberzadeh, Shapour

    2016-04-01

    Altered pattern of muscle activity is commonly seen with chronic neck pain (CNP). However, limited investigations have been done on dorsal neck muscles' activity pattern while performing upper limb tasks in patients with CNP. To investigate dorsal neck muscles' thickness changes during isometric contraction of shoulder muscles. Case-control study. This study investigated dorsal neck muscles' thickness changes during isometric contraction of shoulder muscles in 20 healthy participants (mean age 27 ± 4.37) and 17 patients with CNP (mean age 29 ± 5.50). Effects of isometric force of shoulder muscles on dorsal neck muscles' thickness changes were also evaluated. Significant muscle × group interaction was observed for the dorsal neck muscles thickness changes (p = 0.008) indicating different pattern of muscle activity in terms of changes in muscle thickness of two groups. Significant main effects of direction was observed (P = 0.003), with the abduction had the greatest impact on changing the dorsal neck muscles thickness. patients with CNP showed altered pattern of muscle thickness changes in comparison to healthy participants. Isometric abduction of shoulder muscles induced the greatest changes of dorsal neck muscles thickness among other force directions. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. Individual Difference Variables and the Effects of Progressive Muscle Relaxation and Analgesic Imagery Interventions on Cancer Pain

    OpenAIRE

    Kwekkeboom, Kristine L.; Wanta, Britt; Bumpus, Molly

    2008-01-01

    Clinicians in acute care settings are often called upon to manage cancer pain unrelieved by medications. Cognitive-behavioral strategies, such as relaxation and imagery, are recommended for cancer pain management; however, there appear to be individual differences in their effects. This pilot study examined variation in pain outcomes achieved with progressive muscle relaxation (PMR) and analgesic imagery interventions among hospitalized patients with cancer pain, and assessed the influence of...

  5. Pressure pain threshold changes after repeated mechano-nociceptive stimulation of the trapezius muscle: possible influence of previous pain experience

    DEFF Research Database (Denmark)

    Sjölund, Bengt H; Persson, Ann L

    2007-01-01

    We examined the relation between repeated noxious pressure over the trapezius muscle and changes in pressure pain thresholds (PPTs) in a before-after trial design. A conditioning series of 30 mechano-nociceptive stimuli was applied manually with a handheld algometer probe, and PPTs were measured...... who had given birth to 1 or several children (Ptested at a second session, a clear correlation of PPT reactions (r=0.527; Pmuscle in healthy females evokes moderate and temporary...... over 1 trapezius muscle (skin anaesthetized) in 27 healthy women before and after the intervention. With a mean stimulation rate of 0.40 Hz and a mean nociceptive stimulation intensity of 1.78 x Threshold, subjects were found to systematically react with a change in PPT, either a decrease...

  6. Myofascial Pain Dysfunction Syndrome (MPDS

    Directory of Open Access Journals (Sweden)

    Hamed Mortazavi

    2010-10-01

    Full Text Available Introduction: Myofascial Pain Dysfunction Syndrome (MPDS is one of the most important causes of the orofacial pain. The main purpose of this study was to evaluate 40 related variables in this regard. Materials and Methods: Thirty nine patients with MPDS were evaluated in this study. Different factors including age, gender, occupation, marital status, sensitivity of masticatory muscles, maximum opening of the mouth, deviation, deflection, involvement of temporomandibular joint, habit, parafunction, malocclusion, neck pain, headache, earache and history of jaw involvement, etc were analyzed in this  evaluation. Results: In our study, 39 patients (32 females and 7 males, 20-40 years old, with the average age of 35 ± 13.32 years were studied. 51% were housewives and 74.4% were married. The most common involvements were Clicking (74.4%, pain in temporomandibular joint (54%, headache (46.2%, earache (41%, neck-pain (35.9%, trouble in the mouth opening (71.8%, malocclusion Class I (74.4%, cross bite and deep bite (25%, clenching (64.1% and involvement of masseter and lateral pterygoid muscle (84%. Conclusion: Since MPDS consists of variable symptoms, it might be very difficult to provide any definite diagnosis and treatment. Therefore the more the specialists extend their knowledge and information about this disorder, the more they will make the best decision in this regard.

  7. Effects of interocclusal distance on bite force and masseter EMG in healthy participants.

    Science.gov (United States)

    Arima, T; Takeuchi, T; Honda, K; Tomonaga, A; Tanosoto, T; Ohata, N; Svensson, P

    2013-12-01

    The aim of this study was to investigate effects of interocclusal distance (IOD) on bite force and masseter electromyographic (EMG) activity during different isometric contraction tasks. Thirty-one healthy participants (14 women and 17 men, 21·2 ± 1·8 years) were recruited. Maximal Voluntary Occlusal Bite Force (MVOBF) between the first molars and masseter EMG activity during all the isometric-biting tasks were measured. The participants were asked to bite at submaximal levels of 20%, 40%, 60% and 80% MVOBF with the use of visual feedback. The thickness of the force transducer was set at 8, 12, 16 and 20 mm (= IOD), and sides were tested in random sequence. MVOBF was significantly higher at 8 mm compared with all other IODs (P EMG (P EMG activity compared with the balancing side (P EMG at any IODs. The results replicated the finding that higher occlusal forces can be generated between the first molars at shorter IODs. The new finding in this study was that an effect of hand dominance could be found on masseter muscle activity during isometric biting. This may suggest that there can be a general dominant side effect on human jaw muscles possibly reflecting differences in motor unit recruitment strategies.

  8. Vitamin D Status Is Not Associated with Outcomes of Experimentally-Induced Muscle Weakness and Pain in Young, Healthy Volunteers

    Directory of Open Access Journals (Sweden)

    Susan M. Ring

    2010-01-01

    Full Text Available Vitamin D receptors have been identified in skeletal muscle; and symptoms of vitamin D deficiency include muscle weakness and pain. Moreover, increased serum 25-hydroxyvitamin D (25(OHD concentrations have been associated with improved muscle function. To further clarify the importance of vitamin D to muscle, we examined the association between vitamin D status and exercise-induced muscle pain and weakness in healthy people. Muscle damage to the elbow flexors was induced with eccentric exercise (EE in 48 individuals (22.5 ± 3.2 yrs. Muscle pain ratings following unloaded movement and peak isometric force (IF were collected before EE and for 4 days post-EE. Linear regression was used to determine if serum 25(OHD was a predictor of any outcome. In males, R2-values from 0.48 to 1.00. R2 for IF ranged from 0 to 0.02 and P-values from 0.48 to 1.00. In females, R2 for pain ratings ranged from 0.01 to 0.11 and P-values from 0.14 to 0.59. R2 for IF ranged from 0 to 0.04 and P-values from 0.41 to 0.90. In conclusion, vitamin D status did not predict muscle pain or strength after EE-induced muscle damage in young healthy men and women.

  9. Differences in pain perception during open muscle biopsy and Bergstroem needle muscle biopsy

    OpenAIRE

    Dengler J; Linke P; Gdynia HJ; Wolf S.; Ludolph AC; Vajkoczy P; Meyer T

    2014-01-01

    Julius Dengler,1 Peter Linke,2 Hans J Gdynia,3 Stefan Wolf,1 Albert C Ludolph,3 Peter Vajkoczy,1 Thomas Meyer2 1Department of Neurosurgery, 2Department of Neurology, Charité – Universitätsmedizin Berlin, Berlin, Germany; 3Department of Neurology, Universitätsklinikum Ulm, Ulm, GermanyPurpose: Open surgical muscle biopsy (OB) and percutaneous Bergstroem needle muscle biopsy (NB) are equally accepted procedures. However, there are no data comparing intrapr...

  10. Groin pain

    Science.gov (United States)

    Pain - groin; Lower abdominal pain; Genital pain; Perineal pain ... Common causes of groin pain include: Pulled muscle, tendon, or ligaments in the leg: This problem often occurs in people who play sports such as ...

  11. Electromyographic power spectrum of jaw muscles during clenching in unilateral temporomandibular joint osteoarthritis patients.

    Science.gov (United States)

    Park, I H; McCall, W D; Chung, J W

    2012-09-01

    The relationship between temporomandibular joints (TMJ) osteoarthritis and masticatory muscle disorders is poorly understood. The data are sparse, the results are conflicting, and electromyographic (EMG) power spectrum analysis has not been used. The aims of this study were to compare the differences in EMG power spectrum during, and pressure pain thresholds (PPTs) before and after, sustained clenching in patients with unilateral TMJ osteoarthritis and healthy control subjects. Nineteen patients with unilateral TMJ osteoarthritis without masticatory muscle pain and 20 control subjects were evaluated. We measured EMG amplitudes at maximum voluntary contraction, median frequency from the EMG power spectrum during sustained clenching at 70% and PPTs before and after the clenching in both temporalis and masseter muscles. There were no significant differences in PPT decrease between muscles or between groups during sustained clenching. There were no significant differences in maximum voluntary contraction EMG activity ratios of affected to unaffected sides between groups, or of masseter to temporalis muscles between affected and unaffected side of patients with TMJ osteoarthritis. Median frequencies decreased from the beginning to the end of the sustained clench, and the interaction between group and clench was significant: the median frequency decrease was larger in the osteoarthritis group. Our results suggested that masticatory muscles of patients with unilateral TMJ osteoarthritis are more easily fatigued during sustained clenching than normal subjects. © 2012 Blackwell Publishing Ltd.

  12. Efficacy of posterolateral hip muscles strengthening on patellofemoral pain

    Directory of Open Access Journals (Sweden)

    Ramandeep Kaur

    2016-07-01

    Results: Significant improvements in VAS and WOMAC scores were observed in both groups from 0th-week to 2nd week and 0-week to 4th-week follow-up (P<0.05. Improvements in VAS and WOMAC scores in group B were superior to those in group A at 4-week follow-up (P<0.05. Conclusions: The present study has concluded that both Group A and Group B were effective in the management of patello-femoral pain but statistically it was concluded that Group B is more effective as compared to Group A. [Int J Res Med Sci 2016; 4(7.000: 2921-2925

  13. EFFECTS OF MUSCLE ENERGY TECHNIQUE ON PAIN AND DISABILITY IN SUBJECTS WITH SI JOINT DYSFUNCTION

    Directory of Open Access Journals (Sweden)

    Deepali Sharma

    2014-02-01

    Full Text Available Background: Low back pain has become one of the most common, and most difficult medical problems costing $24 billion (1990 for treatment. With the consideration of costs of disability, lost workforce productivity and other related factors, the cost of society rises to $50 billion. In spite of this, disability due to low back pain has continued to rise. Aims and objectives: The incidence of lower back pain in humans parallels the incidence of the common cold, with a lifetime rate approaching 95%.Several attempts have been made to treat the chronic low back pain due to SIJ dysfunction with mobilization, manipulation and other treatment methods. Methodology: 20 men and women were recruited for the study on the basis of Unilateral back pain experiencing around or near sacral sulcus and Positive muscle length tests for piriformis, Erecter Spinae, Quadratus Lumborum. All the subjects were randomly assigned into two groups where Subjects in group A undergone MET and mobilization and Group B was treated only with mobilization of SI joint. Outcome was measured on first day and then after 1 and 2 week from each subjects pain and disability by Visual analogue scale and modified oswestry disability questionnaire (MODI Results: Paired t test was used to analyse the values of VAS and MODI within the group. ANOVA was used for between the analyses of VAS and MODI for both the groups. Conclusion: MET and mobilisation are both effective in treating chronic low back pain due to sacroiliac joint dysfunction

  14. Clinical effects of deep cervical flexor muscle activation in patients with chronic neck pain.

    Science.gov (United States)

    Kim, Jin Young; Kwag, Kwang Il

    2016-01-01

    [Purpose] The purpose of this study was to investigate clinical effects of deep cervical flexor (DCF) muscles exercise on pain, Neck Disability Index (NDI), and neck and shoulder postures in patients with chronic neck pain. [Subjects and Methods] Twenty-eight patients with chronic neck pain were randomly assigned into either the general strengthening exercise (GSE) group or the DCF activation group as control and experimental groups, respectively. All exercises were performed three times per week over 4 weeks. NDI and numeric rating scale (NRS) score for pain were determined and radiological assessment of neck-shoulder postures (head tilt angle [HTA], neck flexion angle [NFA], and forward shoulder angle [FSA]) was performed before (baseline), 4 weeks after, and 8 weeks after exercise in order to directly compare the exercise effects between the groups. [Results] In the DCF group, the NDI, NRS score, and neck-shoulder postures (analyzed by uisng HTA, NFA, and FSA) were significantly improved. [Conclusion] DCF activation exercise was effective to alleviate pain, recover functions, and correct forward head posture in the patients with neck pain. Hence, it might be recommended in the rehabilitation of patients with chronic neck pain.

  15. Efficacy Of Electroacupuncture For Myofascial Pain In The Upper Trapezius Muscle: A Case Series.

    OpenAIRE

    Aranha,Maria F. M.; ALVES,MARCELO C.; Bérzin, Fausto; Gavião, Maria B. D.

    2015-01-01

    BACKGROUND: Electroacupunture (EA) includes the passage of an electrical current through the acupuncture needle and is commonly used for pain relief. OBJECTIVE: To evaluate the EA treatment effects for myofascial pain in the upper trapezius muscle. METHODS: Twenty women aged ranging from 18 to 40 years (mean=24.95; SD=5.88 years), with a body mass index ranging from 19 to 25 kg/m2 (mean=22.33; SD=0.56 kg/m2), with regular menstrual cycles controlled by oral contraceptive, local or referred pa...

  16. Does Deep Cervical Flexor Muscle Training Affect Pain Pressure Thresholds of Myofascial Trigger Points in Patients with Chronic Neck Pain? A Prospective Randomized Controlled Trial

    Directory of Open Access Journals (Sweden)

    Pavlos Bobos

    2016-01-01

    Full Text Available Background. We need to understand more about how DNF performs in different contexts and whether it affects the pain threshold over myofascial trigger points (MTrPs. Purpose. The objectives were to investigate the effect of neck muscles training on disability and pain and on pain threshold over MTrPs in people with chronic neck pain. Methods. Patients with chronic neck pain were eligible for participation with a Neck Disability Index (NDI score of over 5/50 and having at least one MTrP on either levator scapulae, upper trapezoid, or splenius capitis muscle. Patients were randomly assigned into either DNF training, superficial neck muscle exercise, or advice group. Generalized linear model (GLM was used to detect differences in treatment groups over time. Results. Out of 67 participants, 60 (47 females, mean age: 39.45 ± 12.67 completed the study. Neck disability and neck pain were improved over time between and within groups (p<0.05. However, no differences were found within and between the therapeutic groups (p<0.05 in the tested muscles’ PPTs and in cervicothoracic angle over a 7-week period. Conclusion. All three groups improved over time. This infers that the pain pathways involved in the neck pain relief are not those involved in pain threshold.

  17. Short Term Effects of Mobilization Techniques on Neck Pain and Deep Neck Flexor Muscle Endurance in Patients with Mechanical Chronic Neck Pain

    Science.gov (United States)

    Kılınç, Hasan Erkan; Harput, Gülcan; Baltacı, Gül; İnce, Deniz İnal

    2014-01-01

    Objectives: The aim of the study was to investigate short term effects of cervical and scapular mobilization techniques on neck pain and deep cervical muscles endurance in chronical mechanical neck pain patients. Methods: 22 chronical mechanic neck pain patients four male 18 female (mean age: mean±sd 35.59± 15.85) were included. Before treatment, neck pain level (visual analog scale) and deep neck flexor muscles endurance (in supine position with digital chronometer) of all patients were evaluated. Cyriax cervical mobilization for 10 minutes and scapular mobilization for 10 repetition 10 sets were performed to patients as treatment protocol. After treatment, 24 hours after and a week after evaluations of neck pain and deep cervical muscles endurance were repeated. Results: Before treatment Neck pain Visual Analog Scale scores was 5.78±1.43 point, 2.80±1.99 point after treatment, 24 hours later 3.36±2.12 point, one week later 3.91±2.24 point. This alteration was found significant statistically (p<0.01). Before treatment deep cervical flexor muscle endurance score was 27.25±17.74 sec, after treatment 39.46±25.20 sec, 24 hours later 38.67±28.43 and one week later 40.11±27.82 sec. This alteration was also found significant statistically (p=0.01). Conclusion: Initially neck pain scores in our subjects decreased quickly, after 24 hours these scores increased but last scores were below first neck pain level in a week follow-up. Deep neck cervical flexor muscles test scores also increased quickly, after 24 hours later this scores were stable along a week. Mobilization techniques are effective methods on neck pain and endurance in chronical mechanic neck pain patients.

  18. Trunk strength and lumbar paraspinal muscle activity during isometric exercise in chronic low-back pain patients and controls.

    Science.gov (United States)

    Cassisi, J E; Robinson, M E; O'Conner, P; MacMillan, M

    1993-02-01

    The purpose of this study was to describe trunk strength and lumbar paraspinal muscle activity across five angles of flexion during isometric exercise and rest in chronic low-back pain patients and control subjects. High muscle tension as measured by surface integrated electromyography is predicted by a muscle spasm model, and low muscle tension is predicted by a muscle deficiency model. Prior lumbar surgery had no affect on peak torque or maximum surface integrated electromyography data. Both groups produced greater torque and less surface integrated electromyography in more flexed positions. Chronic low-back pain patients exhibited lower peak torque and lower maximum surface integrated electromyography bilaterally during isometric extension effort across all angles. A muscle deficiency model of chronic low back pain was supported by these data and a muscle spasm model was not supported. Discriminant analyses indicated that monitoring maximum surface integrated electromyography of lumbar muscles during isometric effort facilitates classification of chronic low-back pain patients. Future directions are discussed in terms of applying psychophysiologic methods to pain rehabilitation.

  19. Atrophy of sacrospinal muscle groups in patients with chronic, diffusely radiating lumbar back pain

    Energy Technology Data Exchange (ETDEWEB)

    Laasonen, E.M.

    1984-01-01

    After surgery necessitated by lumbar back pain syndromes, radiolucency verified by CT may appear in the sacrospinal muscle group on the operate side. This radiolucency represents muscular atrophy and is in its most severe form a result of the replacement of muscle tissue with adipose tissue. Such muscular atrophy appeared in the present series in 31 out of all 156 patients (19.9%) and in 29 out of 94 patients operated on because of radiating lumbar back pain (30.9%). The radiological appearance, extent, and HU values of this muscular atrophy are presented in detail. Only weak correlations with the multitude of clinical symptoms and signs were found in this retrospective study. The effects of irreversible muscular atrophy on the indications for surgery and physiotherapy are discussed.

  20. Diabetic Muscle Infarction: A Rare Cause of Acute Limb Pain in Dialysis Patients

    OpenAIRE

    De Vlieger, G.; B. Bammens; Claus, F; De Vos, R; Claes, K.

    2013-01-01

    Diabetic muscle infarction is a rare microangiopathic complication occurring in patients with advanced diabetes mellitus. Diabetic patients with chronic kidney disease stage Vd are prone to develop this complication. The presenting symptom is a localized painful swelling of the affected limb. Symptoms usually resolve spontaneously during the following weeks, but frequent relapse can occur and in some cases swelling may lead to compartment syndrome. Biochemical blood analyses show an elevated ...

  1. Quantification of deep and superficial sensibility in saline-induced muscle pain--a psychophysical study.

    Science.gov (United States)

    Graven-Nielsen, T; Fenger-Grøn, L S; Svensson, P; Steengaard-Pedersen, K; Arendt-Nielsen, L; Staehelin Jensen, T

    1998-01-01

    The aim of the present study was to study the sensibility in the area of saline-induced muscle pain. In three experiments, ten subjects were exposed to computer-controlled infusion of 0.5 ml isotonic (0.9%) or hypertonic (9%) saline into the anterior tibial muscle. The pain intensity was assessed on a visual analogue scale (VAS). The pain threshold (PT) to pressure and electrical stimulation in muscle and subcutaneous tissues was determined. Three experiments were performed in which infusion of hypertonic saline produced significantly higher VAS scores than isotonic saline. In all three experiments, there was no significant difference in PT obtained after infusion of isotonic saline compared with infusion of hypertonic saline. In experiment 1, the PT was determined at the infusion site and 4 cm from the infusion site. At the infusion site, the pressure PT decreased (-19 +/- 2%) 1, 3, 5, 7 and 9 min after infusion of isotonic and hypertonic saline, but remained unchanged 4 cm from the infusion site. The intramuscular electrical PT at the infusion site and 4 cm from the infusion site increased significantly (29 +/- 6%) 5, 7 and 9 min after saline infusion. In experiment 2, the pressure PT and the intramuscular electrical PT were recorded after two infusions of saline separated by 1 day. The day after the first infusion, the pressure PT was decreased compared with the PT before the first infusion, but the electrical PT was not affected. Moreover, the hypertonic saline infusion given on the second day produced significantly higher (130 +/- 50%) VAS scores than the infusion given on the first day. In experiment 3, the PT was determined in the subcutaneous tissue, but no significant effects of saline infusion were found. The present placebo-controlled experiments failed to show muscular or subcutaneous hyperalgesia after saline-induced muscle pain per se.

  2. Effects of proprioceptive circuit exercise on knee joint pain and muscle function in patients with knee osteoarthritis.

    Science.gov (United States)

    Ju, Sung-Bum; Park, Gi Duck; Kim, Sang-Soo

    2015-08-01

    [Purpose] This study applied proprioceptive circuit exercise to patients with degenerative knee osteoarthritis and examined its effects on knee joint muscle function and the level of pain. [Subjects] In this study, 14 patients with knee osteoarthritis in two groups, a proprioceptive circuit exercise group (n = 7) and control group (n = 7), were examined. [Methods] IsoMed 2000 (D&R Ferstl GmbH, Hemau, Germany) was used to assess knee joint muscle function, and a Visual Analog Scale was used to measure pain level. [Results] In the proprioceptive circuit exercise group, knee joint muscle function and pain levels improved significantly, whereas in the control group, no significant improvement was observed. [Conclusion] A proprioceptive circuit exercise may be an effective way to strengthen knee joint muscle function and reduce pain in patients with knee osteoarthritis.

  3. Prevalence and anatomical location of muscle tenderness in adults with nonspecific neck/shoulder pain

    Directory of Open Access Journals (Sweden)

    Mortensen Ole S

    2011-07-01

    Full Text Available Abstract Background Many adults experience bothersome neck/shoulder pain. While research and treatment strategies often focus on the upper trapezius, other neck/shoulder muscles may be affected as well. The aim of the present study is to evaluate the prevalence and anatomical location of muscle tenderness in adults with nonspecific neck/shoulder pain. Methods Clinical neck/shoulder examination at two large office workplaces in Copenhagen, Denmark. 174 women and 24 men (aged 25-65 years with nonspecific neck/shoulder pain for a duration of at least 30 days during the previous year and a pain intensity of at least 2 on a modified VAS-scale of 0-10 participated. Exclusion criteria were traumatic injuries or other serious chronic disease. Using a standardized finger pressure of 2 kg, palpable tenderness were performed of eight anatomical neck/shoulder locations in the left and right side on a scale of 'no tenderness', 'some tenderness' and 'severe tenderness'. Results In women, the levator scapulae, neck extensors and infraspinatus showed the highest prevalence of severe tenderness (18-30%. In comparison, the prevalence of severe tenderness in the upper trapezius, occipital border and supraspinatus was 13-19%. Severe tenderness of the medial deltoid was least prevalent (0-1%. In men, the prevalence of severe tenderness in the levator scapulae was 13-21%, and ranged between 0-8% in the remainder of the examined anatomical locations. Conclusions A high prevalence of tenderness exists in several anatomical locations of the neck/shoulder complex among adults with nonspecific neck/shoulder pain. Future research should focus on several neck/shoulder muscles, including the levator scapulae, neck extensors and infraspinatus, and not only the upper trapezius. Trial Registration ISRCTN60264809

  4. Exercise prevents development of autonomic dysregulation and hyperalgesia in a mouse model of chronic muscle pain.

    Science.gov (United States)

    Sabharwal, Rasna; Rasmussen, Lynn; Sluka, Kathleen A; Chapleau, Mark W

    2016-02-01

    Chronic musculoskeletal pain (CMP) conditions, like fibromyalgia, are associated with widespread pain and alterations in autonomic functions. Regular physical activity prevents the development of CMP and can reduce autonomic dysfunction. We tested if there were alterations in autonomic function of sedentary mice with CMP, and whether exercise reduced the autonomic dysfunction and pain induced by CMP. Chronic musculoskeletal pain was induced by 2 intramuscular injections of pH 5.0 in combination with a single fatiguing exercise task. A running wheel was placed into cages so that the mouse had free access to it for either 5 days or 8 weeks (exercise groups) and these animals were compared to sedentary mice without running wheels. Autonomic function and nociceptive withdrawal thresholds of the paw and muscle were assessed before and after induction of CMP in exercised and sedentary mice. In sedentary mice, we show decreased baroreflex sensitivity, increased blood pressure variability, decreased heart rate variability, and decreased withdrawal thresholds of the paw and muscle 24 hours after induction of CMP. There were no sex differences after induction of the CMP in any outcome measure. We further show that both 5 days and 8 weeks of physical activity prevent the development of autonomic dysfunction and decreases in withdrawal threshold induced by CMP. Thus, this study uniquely shows the development of autonomic dysfunction in animals with chronic muscle hyperalgesia, which can be prevented with as little as 5 days of physical activity, and suggest that physical activity may prevent the development of pain and autonomic dysfunction in people with CMP.

  5. Muscle trigger points and pressure pain sensitivity maps of the feet in women with fibromyalgia syndrome

    DEFF Research Database (Denmark)

    Tornero-Caballero, Maria C.; Salom-Moreno, Jaime; Cigarán-Méndez, Margarita

    2016-01-01

    comparable healthy women participated. TrPs within the flexor hallucis brevis, adductor hallucis, dorsal interossei, extensor digitorum brevis, and quadratus plantae, as well as external and internal gastrocnemius, were explored. Pressure pain thresholds (PPTs) were assessed in a blind manner over seven...... locations on each foot. Topographical pressure sensitivity maps of the plantar region were generated using the averaged PPT of each location. RESULTS : The prevalence rate of foot pain was 63% (n = 32). The number of active TrPs for each FMS woman with foot pain was 5 ± 1.5 without any latent TrPs. Women...... with FMS without foot pain and healthy controls had only latent TrPs (2.2 ± 0.8 and 1.5 ± 1.3, respectively). Active TrPs in the flexor hallucis brevis and adductor hallucis muscles were the most prevalent. Topographical pressure pain sensitivity maps revealed that FMS women with foot pain had lower PPT...

  6. The Association between Imaging Parameters of the Paraspinal Muscles, Spinal Degeneration, and Low Back Pain

    Science.gov (United States)

    Carmeli, Eli

    2017-01-01

    This narrative review investigated imaging parameters of the paraspinal muscles and their association with spinal degenerative features and low back pain (LBP) found in the literature. Three principal signs of muscle degeneration were detected on imaging: decreased muscle size, decreased radiographic density, and increased fat deposits. Men have a higher density of paraspinal muscles than women, younger individuals have a higher density than older ones, and lean individuals have a higher density than those with an increased body mass index. Fatty infiltration appears to be a late stage of muscular degeneration and can be measured noninvasively by an MRI scan. Fatty infiltration in the lumbar multifidus is common in adults and is strongly associated with LBP, especially in women, independent of body composition. Fatty infiltration develops in areas where most degenerative changes are found. MR spectroscopy studies have corroborated that the lumbar multifidus in LBP subjects has a significantly higher fat content than asymptomatic controls. There is a strong need for establishing uniform methods of evaluating normal parameters and degenerative changes of the paraspinal muscles. Additional imaging studies are needed to improve the understanding of the association and causal relationships between LBP, spinal degeneration, and changes in the paraspinal muscles. PMID:28409152

  7. The Association between Imaging Parameters of the Paraspinal Muscles, Spinal Degeneration, and Low Back Pain

    Directory of Open Access Journals (Sweden)

    Leonid Kalichman

    2017-01-01

    Full Text Available This narrative review investigated imaging parameters of the paraspinal muscles and their association with spinal degenerative features and low back pain (LBP found in the literature. Three principal signs of muscle degeneration were detected on imaging: decreased muscle size, decreased radiographic density, and increased fat deposits. Men have a higher density of paraspinal muscles than women, younger individuals have a higher density than older ones, and lean individuals have a higher density than those with an increased body mass index. Fatty infiltration appears to be a late stage of muscular degeneration and can be measured noninvasively by an MRI scan. Fatty infiltration in the lumbar multifidus is common in adults and is strongly associated with LBP, especially in women, independent of body composition. Fatty infiltration develops in areas where most degenerative changes are found. MR spectroscopy studies have corroborated that the lumbar multifidus in LBP subjects has a significantly higher fat content than asymptomatic controls. There is a strong need for establishing uniform methods of evaluating normal parameters and degenerative changes of the paraspinal muscles. Additional imaging studies are needed to improve the understanding of the association and causal relationships between LBP, spinal degeneration, and changes in the paraspinal muscles.

  8. [Mechanisms of muscle pain : significance of trigger points and tender points].

    Science.gov (United States)

    Brezinschek, H-P

    2008-12-01

    Fibromyalgia syndrome (FMS) and myofascial pain syndrome (MPS) belong to the group of chronic non-inflammatory pain syndromes affecting muscles and tendinous insertions. Important criteria in the diagnosis of both diseases are the presence of "tender points" and "trigger points". According to ACR criteria FMS is characterized by the presence of tender points whereas trigger points are typically found in MPS.The main difference is that until now tender points could only be defined in terms of their localization, whereas trigger points can be found upon palpation which may cause a specific referred pain pattern. In addition, analysis of trigger points by microdialysis demonstrated elevated levels of pro-inflammatory substances at these sites. Moreover, local treatment of trigger points either by manipulative therapy or injection appears to be most effective for prompt relief of symptoms.

  9. Rapid muscle activation and force capacity in conditions of chronic musculoskeletal pain

    DEFF Research Database (Denmark)

    Andersen, Lars L; Holtermann, Andreas; Jørgensen, Marie B

    2008-01-01

    during the stable high-force phase of maximal voluntary shoulder abduction, whereas rapid capacity was determined as the steepest slope of the torque-time and EMG-time curves, defined as rate of torque development and rate of EMG rise. Intensity of pain was registered prior to the test on a visual......-analogue-scale. FINDINGS: Peak torque was 18% lower at 115 degrees shoulder joint angle in women with myalgia compared with healthy controls (PRate of torque development was 33-54% lower (P...BACKGROUND: The association between musculoskeletal pain and decreased maximal muscle strength capacity has been extensively studied, but knowledge about functional rapid force capacity in conditions of chronic musculoskeletal pain is lacking. The objective of this study is to investigate rapid...

  10. The impact of neurodynamic testing on the perception of experimentally induced muscle pain.

    Science.gov (United States)

    Coppieters, Michel W; Kurz, Kimberly; Mortensen, Thor Einar; Richards, Nicola L; Skaret, Ingrid A; McLaughlin, Laurie M; Hodges, Paul W

    2005-02-01

    Neurodynamic tests such as the straight leg raising (SLR) and slump test are frequently used for assessment of mechanosensitivity of neural tissues. However, there is ongoing debate in the literature regarding the contributions of neural and non-neural tissues to the elicited symptoms because many structures are affected by these tests. Sensitizing manoeuvres are limb or spinal movements added to neurodynamic tests, which aim to identify the origin of the symptoms by preferentially loading or unloading neural structures. A prerequisite for the use of sensitizing manoeuvres to identify neural involvement is that the addition of sensitizing manoeuvres has no impact on pain perception when the origin of the pain is non-neural. In this study, experimental muscle pain was induced by injection of hypertonic saline in tibialis anterior or soleus in 25 asymptomatic, naive volunteers. A first experiment investigated the impact of hip adduction, abduction, medial and lateral rotation in the SLR position. In a second experiment, the different stages of the slump test were examined. The intensity and area of experimentally induced muscle pain did not increase when sensitizing manoeuvres were added to the SLR or throughout the successive stages of the slump test. The findings of this study lend support to the validity of the use of sensitizing manoeuvres during neurodynamic testing.

  11. Hip and knee muscle function following aerobic exercise in individuals with patellofemoral pain syndrome.

    Science.gov (United States)

    Ott, Brittany; Cosby, Nicole L; Grindstaff, Terry L; Hart, Joseph M

    2011-08-01

    Patellofemoral pain syndrome (PFPS) is a commonly experienced knee disorder that can result in altered muscle activation of the surrounding musculature. There is little evidence on effects of aerobic exercise on quadriceps torque and EMG activation of the vastus medialis obliquus (VMO), vastus lateralis (VL), and gluteus medius (GM). In this study 20 healthy individuals and 20 patients with PFPS had measures of torque and muscle activation taken following aerobic exercise. A modified Balke-Ware protocol was used for the exercise intervention. Baseline and post-aerobic measurements of knee extension torque and VMO, VL, and GM activation during a single leg anterior reaching task. These measurements were only taken on the injured limb. Following exercise, knee extension torque was lower in PFPS patients when compared to controls (p=0.03). Patients reporting no pain after exercise experienced decreases (p=0.021) in GM activation following exercise. There was a decrease in VMO (p=0.010) and VL (p=0.021) activation in PFPS patients with elevated knee pain. Recreationally active individuals with PFPS may experience different responses in the quadriceps and GM after exercise. Responses may be confounded by whether or not pain is exacerbated by exercise.

  12. Effect of self-myofascial release on myofascial pain, muscle flexibility, and strength: A narrative review.

    Science.gov (United States)

    Kalichman, Leonid; Ben David, Chen

    2017-04-01

    Numerous techniques have been employed to treat myofascial pain syndrome. Self-myofascial release (SMFR) is a relatively new technique of soft tissue mobilization. The simplicity and portability of the SMFR tools allow it to be easily implemented in any type of fitness or rehabilitation program. It is an active method and can be used by anyone at home or at the workplace. To review the current methods of SMFR, their mechanisms, and efficacy in treating myofascial pain, improving muscle flexibility and strength. PubMed, Google Scholar, and PEDro databases were searched without search limitations from inception until July 2016 for terms relating to SMFR. During the past decade, therapists and fitness professionals have implemented SMFR mainly via foam rolling as a recovery or maintenance tool. Researchers observed a significant increase in the joint range of motion after using the SMFR technique and no decrease in muscle force or changes in performance after treatment with SMFR. SMFR has been widely used by health-care professionals in treating myofascial pain. However, we found no clinical trials which evaluated the influence of SMFR on myofascial pain. There is an acute need for these trials to evaluate the efficacy and effectiveness of SMFR in the treatment of the myofascial syndrome. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Reorganised motor control strategies of trunk muscles due to acute low back pain.

    Science.gov (United States)

    Hirata, R P; Salomoni, S E; Christensen, S W; Graven-Nielsen, T

    2015-06-01

    This study assessed how the low back motor control strategies were affected by experimental pain. In twelve volunteers the right m. longissimus was injected by hypertonic and isotonic (control) saline. The pain intensity was assessed on a visual analog scale (VAS). Subjects were seated on a custom-designed chair including a 3-dimensional force sensor adjusted to the segmental height of T1. Electromyography (EMG) was recorded bilaterally from longissimus, multifidus, rectus abdominis, and external oblique muscles. Isometric trunk extensions were performed before, during, and after the saline injections at 5%, 10%, and 20% of maximum voluntary contraction force. Visual feedback of the extension force was provided whereas the tangential force components were recorded. Compared with isotonic saline, VAS scores were higher following hypertonic saline injections (Pback pain reduced the EMG activity bilaterally of the rectus abdominis muscles during contractions at 10% and 20% MVC (Ppain compared with the non-painful condition (Ppain was sufficient to maintain the quality of the task performance; however the long-term consequence of such adaptation is unknown and may overload other structures. Copyright © 2015 Elsevier B.V. All rights reserved.

  14. [Etiological analysis and significance of anterior knee pain induced by gluteal muscles contracture].

    Science.gov (United States)

    Zhao, Gang; Liu, Yu-jie; Wang, Jun-liang; Qi, Wei; Qu, Feng; Yuan, Bang-tuo; Wang, Jiang-tao; Shen, Xue-zhen; Liu, Yang; Zhu, Juan-li

    2014-12-01

    To explore causes of gluteal muscle contracture induced anterior knee pain and curative effect of arthroscopic release. From March 2002 to August 2013,36 patients with gluteal muscle contracture induced anterior knee pain were treated, including 15 males, 21 females, aged from 9 to 40 years old with an average (18.7±7.2) years old; the courses of diseases ranged from 4 to 30 years. The clinical manifestations involved limited to symmelia, positive Ober sign, buttocks touch contracture belts, knee and patella slide to lateral when doing squat activities. All patients were performed gluteal muscle contracture release under arthroscopic. Postoperative complications were observed, Kujala scoring before and after operation was used for compare curative effect. All patients were followed up with an average of 29 months. The incision were healed well, and no complications were occurred. Postoperative Kujala score were improved more than preoperative. Gluteal muscle contracture release could alleviate hypertension of lateral patella, and palys an important role in preventing patellofemoral arthritis.

  15. The effects of gluteus muscle strengthening exercise and lumbar stabilization exercise on lumbar muscle strength and balance in chronic low back pain patients.

    Science.gov (United States)

    Jeong, Ui-Cheol; Sim, Jae-Heon; Kim, Cheol-Yong; Hwang-Bo, Gak; Nam, Chan-Woo

    2015-12-01

    [Purpose] The aim of this study was to examine the effects of exercise to strengthen the muscles of the hip together with lumbar segmental stabilization exercise on the lumbar disability index, lumbar muscle strength, and balance. [Subjects and Methods] This study randomly and equally assigned 40 participants who provided written consent to participate in this study to a lumbar segmental stabilization exercise plus exercise to strengthen the muscles of the gluteus group (SMG + LES group) and a lumbar segmental stabilization exercise group. [Results] Each evaluation item showed a statistically significant effect. [Conclusion] Clinical application of exercise in this study showed that lumbar segmental stabilization exercise plus exercise to strengthen the muscles of the gluteus resulted in a greater decrease in low back pain disability index and increase in lumbar muscle strength and balance ability than lumbar segmental stabilization exercise in chronic low back pain patients receiving the exercise treatments during the same period.

  16. Efficacy of kinesio tape application on pain and muscle strength in patients with myofascial pain syndrome: a placebo-controlled trial.

    Science.gov (United States)

    Öztürk, Gülcan; Külcü, Duygu Geler; Mesci, Nilgün; Şilte, Ayşe Duygu; Aydog, Ece

    2016-04-01

    [Purpose] The purpose of this study was to determine the short- and mid-term effects of Kinesio taping on the trapezius muscle in individuals with myofascial pain syndrome. [Subjects and Methods] Thirty-seven patients with active upper trapezius myofascial trigger points were randomly divided to 2 groups: group 1 received Kinesio taping for the upper trapezius muscle, and group 2 received a sham Kinesio taping application. Neck pain (Visual Analog Scale and pressure algometry) and trapezius muscle strength data were collected at baseline, immediately after Kinesio taping application, and at one month follow-up. [Results] The mean changes in Visual Analog Scale scores were significantly different between groups at T2 and T1, with less pain in group 1. The mean changes in algometry scores were significantly different between groups at T3 compared with T2 in favor of group 1. The mean changes in trapezius muscle strength were significantly different between the groups at T2 compared with T1 in favor of group 1. [Conclusion] Patients with myofascial pain syndrome receiving an application of Kinesio taping exhibited statistically significant improvements in pain and upper trapezius muscle strength.

  17. Efficacy of kinesio tape application on pain and muscle strength in patients with myofascial pain syndrome: a placebo-controlled trial

    Science.gov (United States)

    Öztürk, Gülcan; Külcü, Duygu Geler; Mesci, Nilgün; Şilte, Ayşe Duygu; Aydog, Ece

    2016-01-01

    [Purpose] The purpose of this study was to determine the short- and mid-term effects of Kinesio taping on the trapezius muscle in individuals with myofascial pain syndrome. [Subjects and Methods] Thirty-seven patients with active upper trapezius myofascial trigger points were randomly divided to 2 groups: group 1 received Kinesio taping for the upper trapezius muscle, and group 2 received a sham Kinesio taping application. Neck pain (Visual Analog Scale and pressure algometry) and trapezius muscle strength data were collected at baseline, immediately after Kinesio taping application, and at one month follow-up. [Results] The mean changes in Visual Analog Scale scores were significantly different between groups at T2 and T1, with less pain in group 1. The mean changes in algometry scores were significantly different between groups at T3 compared with T2 in favor of group 1. The mean changes in trapezius muscle strength were significantly different between the groups at T2 compared with T1 in favor of group 1. [Conclusion] Patients with myofascial pain syndrome receiving an application of Kinesio taping exhibited statistically significant improvements in pain and upper trapezius muscle strength. PMID:27190430

  18. Effects of a worksite supervised adapted physical activity program on trunk muscle endurance, flexibility and pain sensitivity among vineyard workers

    DEFF Research Database (Denmark)

    Balaguier, Romain; Madeleine, Pascal; Rose-Dulcina, Kevin

    2017-01-01

    OBJECTIVES: In viticulture, the prevalence of low back pain is particularly high among vineyard workers exposed to sustained and awkward postures. One promising setting for low back pain prevention resides in the implementation of workplace physical activity. METHODS: This non-randomized pilot...... was assessed using flexibility tests for the trunk, along with trunk muscle flexor and extensor endurance tests. Finally, pain sensitivity was evaluated by assessing pressure pain thresholds over 14 anatomical locations in the low back region. RESULTS: For the intervention group, the endurance of the trunk...... of worksite supervised adapted physical activity and most likely, offer a new promising approach to prevent low back pain among vineyard-workers....

  19. Contrasting phenotypes of putative proprioceptive and nociceptive trigeminal neurons innervating jaw muscle in rat

    Directory of Open Access Journals (Sweden)

    Connor Mark

    2005-10-01

    Full Text Available Abstract Background Despite the clinical significance of muscle pain, and the extensive investigation of the properties of muscle afferent fibers, there has been little study of the ion channels on sensory neurons that innervate muscle. In this study, we have fluorescently tagged sensory neurons that innervate the masseter muscle, which is unique because cell bodies for its muscle spindles are in a brainstem nucleus (mesencephalic nucleus of the 5th cranial nerve, MeV while all its other sensory afferents are in the trigeminal ganglion (TG. We examine the hypothesis that certain molecules proposed to be used selectively by nociceptors fail to express on muscle spindles afferents but appear on other afferents from the same muscle. Results MeV muscle afferents perfectly fit expectations of cells with a non-nociceptive sensory modality: Opiates failed to inhibit calcium channel currents (ICa in 90% of MeV neurons, although ICa were inhibited by GABAB receptor activation. All MeV afferents had brief (1 msec action potentials driven solely by tetrodotoxin (TTX-sensitive Na channels and no MeV afferent expressed either of three ion channels (TRPV1, P2X3, and ASIC3 thought to be transducers for nociceptive stimuli, although they did express other ATP and acid-sensing channels. Trigeminal masseter afferents were much more diverse. Virtually all of them expressed at least one, and often several, of the three putative nociceptive transducer channels, but the mix varied from cell to cell. Calcium currents in 80% of the neurons were measurably inhibited by μ-opioids, but the extent of inhibition varied greatly. Almost all TG masseter afferents expressed some TTX-insensitive sodium currents, but the amount compared to TTX sensitive sodium current varied, as did the duration of action potentials. Conclusion Most masseter muscle afferents that are not muscle spindle afferents express molecules that are considered characteristic of nociceptors, but these

  20. Neural Mechanisms of Temporomandibular Joint and Masticatory Muscle Pain: A Possible Role for Peripheral Glutamate Receptor Mechanisms

    Directory of Open Access Journals (Sweden)

    David K Lam

    2005-01-01

    Full Text Available The purpose of the present review is to correlate recent knowledge of the role of peripheral ionotropic glutamate receptors in the temporomandibular joint and muscle pain from animal and human experimental pain models with findings in patients. Chronic pain is common, and many people suffer from chronic pain conditions involving deep craniofacial tissues such as temporomandibular disorders or fibromyalgia. Animal and human studies have indicated that the activation of peripheral ionotropic glutamate receptors in deep craniofacial tissues may contribute to muscle and temporomandibular joint pain and that sex differences in the activation of glutamate receptors may be involved in the female predominance in temporomandibular disorders and fibromyalgia. A peripheral mechanism involving autocrine and/or paracrine regulation of nociceptive neuronal excitability via injury or inflammation-induced release of glutamate into peripheral tissues that may contribute to the development of craniofacial pain is proposed.

  1. Motor unit action potential rate and motor unit action potential shape properties in subjects with work-related muscle pain

    NARCIS (Netherlands)

    Kallenberg, Laura A.C.; Hermens, Hermie J.

    2006-01-01

    The objective of this study was to investigate differences in motor control of the trapezius muscle in cases with work-related chronic pain, compared to healthy controls. Ten cases with chronic pain and 13 controls participated in the study. Electromyographic (EMG) signals were recorded from the upp

  2. Experimental muscle pain during a forward lunge--the effects on knee joint dynamics and electromyographic activity

    DEFF Research Database (Denmark)

    Henriksen, Marius; Alkjaer, T; Simonsen, Erik Bruun

    2009-01-01

    OBJECTIVE: The purpose of this study was to investigate whether the knee joint dynamics during a forward lunge could be modulated by experimentally induced vastus medialis pain in healthy subjects. DESIGN: Randomised cross-over study. SETTING: Biomechanical movement laboratory. PARTICIPANTS: 20 h...... of muscle pain and prevention of injuries during activities involving the knee joint....

  3. One-year evaluation of the effect of physical therapy for masticatory muscle pain : A randomized controlled trial

    NARCIS (Netherlands)

    Craane, B.; Dijkstra, P. U.; Stappaerts, K.; De Laat, A.

    2012-01-01

    Physical therapy is widely used to decrease pain and restore function in patients suffering from masticatory muscle pain. Controlled studies on its efficacy are scarce. This study evaluated the 1-year effect of a 6-week physical therapy programme in a single blind, randomized, controlled trial. Fift

  4. Voluntary activation of the trapezius muscle in cases with neck/shoulder pain compared to healthy controls

    DEFF Research Database (Denmark)

    Bech, Katrine Tholstrup; Larsen, Camilla Marie; Sjøgaard, Gisela

    2017-01-01

    Subjects reporting neck/shoulder pain have been shown to generate less force during maximal voluntary isometric contractions (MVC) of the shoulder muscles compared to healthy controls. This has been suggested to be caused by a pain-related decrease in voluntary activation (VA) rather than lack of...

  5. Distribution of myogenic progenitor cells and myonuclei is altered in women with vs. those without chronically painful trapezius muscle

    DEFF Research Database (Denmark)

    Mackey, Abigail; Andersen, Lars L; Frandsen, Ulrik

    2010-01-01

    It is hypothesized that repeated recruitment of low-threshold motor units is an underlying cause of chronic pain in trapezius myalgia. This study investigated the distribution of satellite cells (SCs), myonuclei, and macrophages in muscle biopsies from the trapezius muscle of 42 women performing ...

  6. Reduction of cervical and respiratory muscle strength in patients with chronic nonspecific neck pain and having moderate to severe disability.

    Science.gov (United States)

    López-de-Uralde-Villanueva, Ibai; Sollano-Vallez, Ernesto; Del Corral, Tamara

    2017-06-11

    To investigate whether patients with chronic nonspecific neck pain and having moderate to severe disability have a greater cervical motor function impairment and respiratory disturbances compared with patients with chronic nonspecific neck pain having mild disability and asymptomatic subjects; and the association between these outcomes in patients with chronic nonspecific neck pain and healthy controls. Cross-sectional study, 44 patients with chronic nonspecific neck pain and 31 healthy subjects participated. The neck disability index was used to divide the patients into 2 groups: 1) mild disability group (scores between 5 and 14 points); and 2) moderate to severe disability group (scores >14 points). Cervical motor function was measured by cervical range of motion, forward head posture, neck flexor, and extensor muscle strength. Respiratory function and maximum respiratory pressures were also measured. Statistically differences were found between the patients with chronic nonspecific neck pain having a moderate to severe disability and the asymptomatic subjects for cervical and respiratory muscle strength. Comparisons between chronic nonspecific neck pain and the asymptomatic groups showed differences for all the variables, except for forward head posture. The regression model determined that strength of cervical flexion explained 36.4 and 45.6% of the variance of maximum inspiratory pressures and maximum expiratory pressures, respectively. Only the chronic nonspecific neck pain group with moderate to severe disability showed differences compared with the healthy subjects. Neck muscle strength could be a good predictor of respiratory muscle function. Implications for rehabilitation Neck pain severity could be closely associated with decreased respiratory pressure in patients with chronic nonspecific neck pain. These findings suggest a new therapeutic approach for patients with moderate to severe disability, such as respiratory muscle training. The regression

  7. Muscle organization in individuals with and without pain and joint dysfunction.

    Science.gov (United States)

    Nickel, J C; Gonzalez, Y M; McCall, W D; Ohrbach, R; Marx, D B; Liu, H; Iwasaki, L R

    2012-06-01

    Central nervous system organization of masticatory muscles determines the magnitude of joint and muscle forces. Validated computer-assisted models of neuromuscular organization during biting were used to determine organization in individuals with and without temporomandibular disorders (TMD). Ninety-one individuals (47 women, 44 men) were assigned to one of four diagnostic groups based on the presence (+) or absence (-) of pain (P) and bilateral temporomandibular joint disc displacement (DD). Electromyography and bite-forces were measured during right and left incisor and molar biting. Two three-dimensional models employing neuromuscular objectives of minimization of joint loads (MJL) or muscle effort (MME) simulated biting tasks. Evaluations of diagnostic group and gender effects on choice of best-fit model were by analysis of variance (ANOVA) and Tukey-Kramer post hoc tests, evaluations of right-left symmetry were by Chi-square and Fisher's exact statistics, and evaluations of model accuracy were by within-subject linear regressions. MME was the best-fit during left molar biting in +DD individuals and incisor biting in men (all p < 0.03). Incisor biting symmetry in muscle organization was significantly higher (p < 0.03) in healthy individuals compared with those with TMD. Within-subject regressions showed that best-fit model errors were similar among groups: 8 to 15% (0.68 ≤ R(2) ≤ 0.74). These computer-assisted models predicted muscle organization during static biting in humans with and without TMDs.

  8. The effect of postural correction on muscle activation amplitudes recorded from the cervicobrachial region.

    Science.gov (United States)

    McLean, Linda

    2005-12-01

    In clinical practice, postural correction is a common treatment approach for individuals with neck and shoulder pain. As chronic static muscle use is thought to be associated with the onset of some neck and shoulder pain syndromes, it is important to understand the impact a postural correction program might have on muscle activation amplitudes in the neck and shoulder regions. Normalized surface electromyographic data were recorded from the levator scapulae, upper trapezius, supraspinatus, posterior deltoid, masseter, rhomboid major, cervical erector spinae, and sternocleidomastoid muscles of the dominant side of each of eighteen healthy subjects. Subjects performed five repetitions of each of four seated typing postures (habitual, corrected, head-forward and slouched) and four standing postures (habitual, corrected, and head-forward and slouched). Repeated-measures analysis of variance models (alpha=0.05) revealed that in sitting postural correction tended to decreased the level of muscle activation required in all muscles studied during seated computer work, however this finding was not statistically significant. Corrected posture in sitting did, however produce a statistically significant reduction in muscle activity compared to forward head posture. Corrected posture in standing required more muscle activity than habitual or forward head posture in the majority of cervicobrachial and jaw muscles, suggesting that a graduated approach to postural correction exercises might be required in order to train the muscles to appropriately withstand the requirements of the task. A surprising finding was that muscle activity levels and postural changes had the largest impact on the masseter muscle, which demonstrated activation levels in the order of 20% maximum voluntary electrical activation.

  9. Neuromuscular electrostimulation techniques: historical aspects and current possibilities in treatment of pain and muscle waisting.

    Science.gov (United States)

    Heidland, August; Fazeli, Gholamreza; Klassen, André; Sebekova, Katarina; Hennemann, Hans; Bahner, Udo; Di Iorio, Biagio

    2013-01-01

    ), acetylcholine and adenosine). The modern electrotherapy of neuromusculo- skeletal pain is based in particular on the following types: transcutaneous electrical nerve stimulation (TENS), percutaneous electrical nerve stimulation (PENS or electro-acupuncture) and spinal cord stimulation (SCS). In mild to moderate pain, TENS and PENS are effective methods, whereas SCS is very useful for therapy of refractory neuropathic or ischemic pain. In 2005, high tone external muscle stimulation (HTEMS) was introduced. In diabetic peripheral neuropathy, its analgesic action was more pronounced than TENS application. HTEMS appeared also to have value in the therapy of symptomatic peripheral neuropathy in end-stage renal disease (ESRD). Besides its pain-relieving effect, electrical stimulation is of major importance for prevention or treatment of muscle dysfunction and sarcopenia. In controlled clinical studies electrical myostimulation (EMS) has been shown to be effective against the sarcopenia of patients with chronic congestive heart disease, diabetes, chronic obstructive pulmonary disease and ESRD.

  10. The relationship beween posture and back muscle endurance in industrial workers with flexion-related low back pain.

    Science.gov (United States)

    O'Sullivan, Peter B; Mitchell, Tim; Bulich, Paul; Waller, Rob; Holte, Johan

    2006-11-01

    This preliminary cross-sectional study was undertaken to determine if there were measurable relationships between posture, back muscle endurance and low back pain (LBP) in industrial workers with a reported history of flexion strain injury and flexion pain provocation. Clinical reports state that subjects with flexion pain disorders of the lumbar spine commonly adopt passive flexed postures such as slump sitting and present with associated dysfunction of the spinal postural stabilising musculature. However, to date there is little empirical evidence to support that patients with back pain, posture their spines differently than pain-free subjects. Subjects included 21 healthy industrial workers and 24 industrial workers with flexion-provoked LBP. Lifestyle information, lumbo-pelvic posture in sitting, standing and lifting, and back muscle endurance were measured. LBP subjects had significantly reduced back muscle endurance (P postured their spines significantly closer to their end of range lumbar flexion in 'usual' sitting than the healthy controls (P back muscle endurance were also identified. There were no significant differences found between the groups for the standing and lifting posture measures. These preliminary results support that a relationship may exist between flexed spinal postures, reduced back muscle endurance, physical inactivity and LBP in subjects with a history of flexion injury and pain.

  11. Muscle activation characteristics in cross-country skiers with a history of anterior compartment pain.

    Science.gov (United States)

    Federolf, Peter; Bakker, Emily

    2012-11-01

    A large proportion of elite cross-country skiers suffer from chronic anterior compartment syndrome (CACS). This study used surface electromyograms (EMGs) to investigate whether differences existed in the activation characteristics of the tibialis anterior muscle between elite cross-country skiers with a history of anterior compartment pain (symptomatic group) and a pain-free control group. Based on self-reported pain symptoms, twelve young, national-level cross-country ski athletes were assigned to a symptomatic group (N = 5), a control group (N = 4), or analyzed individually if their diagnosis was not certain (N = 3). During skating, EMGs were recorded on five lower leg muscles. The relative increase in EMG power per step when increasing the effort level of skating was larger in the symptomatic group than in the control group for tibialis anterior (143 +/- 12% vs. 125 +/- 23%; Cohen's d = 1.17), peroneus longus (123 +/- 24% vs. 107 +/- 6%; d = 0.91), and gastrocnemius lateralis (167 +/- 51% vs. 117 +/- 12%; d = 1.64). The symptomatic group showed more power in the lower frequency bands of the tibialis anterior's EMG spectra (p 0.2). Within the step cycle, these differences appeared in the swing phase and in the gliding phase during single leg support. The observed differences in the EMG spectra may serve as an early identification of athletes who are at risk of developing CACS.

  12. Rare Case of Complete Fatty Degeneration of the Paraspinal Muscle in a Patient with Low Back Pain

    Directory of Open Access Journals (Sweden)

    Ibrahim Atci

    2014-12-01

    Full Text Available The ethiopathogenesis of low back pain cannot always be demonstrated and sometimes clinicians cannot establish a relationship between clinical symptoms and radiological examinations. Clinicians tend to focus on vertebral body, intervertebral discs, and facet joints on imaging in low back pain. However, the paravertebral muscles that play an important role in lumbar spine stabilization should not be underestimated on imaging. The increase in the amount of fat deposited in the lumbar region and the reduction of muscle mass are macroscopic findings of muscle degeneration. In this case report, we present a patient with chronic low back pain who had been reported to have no pathological findings except 2 levels of bulging on previous imaging and who was then diagnosed as having complete fatty degeneration and atrophy of the paravertebral muscles after reevaluation of her imaging results.

  13. Center of Pressure Displacement of Standing Posture during Rapid Movements Is Reorganised Due to Experimental Lower Extremity Muscle Pain.

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    Shinichiro Shiozawa

    Full Text Available Postural control during rapid movements may be impaired due to musculoskeletal pain. The purpose of this study was to investigate the effect of experimental knee-related muscle pain on the center of pressure (CoP displacement in a reaction time task condition.Nine healthy males performed two reaction time tasks (dominant side shoulder flexion and bilateral heel lift before, during, and after experimental pain induced in the dominant side vastus medialis or the tibialis anterior muscles by hypertonic saline injections. The CoP displacement was extracted from the ipsilateral and contralateral side by two force plates and the net CoP displacement was calculated.Compared with non-painful sessions, tibialis anterior muscle pain during the peak and peak-to-peak displacement for the CoP during anticipatory postural adjustments (APAs of the shoulder task reduced the peak-to-peak displacement of the net CoP in the medial-lateral direction (P<0.05. Tibialis anterior and vastus medialis muscle pain during shoulder flexion task reduced the anterior-posterior peak-to-peak displacement in the ipsilateral side (P<0.05.The central nervous system in healthy individuals was sufficiently robust in maintaining the APA characteristics during pain, although the displacement of net and ipsilateral CoP in the medial-lateral and anterior-posterior directions during unilateral fast shoulder movement was altered.

  14. Mental Status as a Common Factor for Masticatory Muscle Pain: A Systematic Review

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    Mieszko Wieckiewicz

    2017-05-01

    Full Text Available Masticatory muscle pain (MMP is the primary reason for chronic non-odontogenic orofacial pain in the human population. MMP has become a considerable social problem, which affects about 12–14% of the adult population and is 1.5–2 times more frequent in women than in men. This term defines a pain which has its origins in the masticatory muscles. Although MMP is typically felt in the face, jaws, and preauricular area, MMP can radiate to the ear, teeth, head, and neck. This systematic review explains the relationship between MMP and common mental states, such as anxiety, depression, mood and stress-related disorders, and is reported in accordance with PRISMA guidelines. We performed a search in the PubMed database for peer-reviewed articles published after November 1st 2006 in the context of MMP and mental states. According to the defined criteria, 38 studies were finally included into the systematic review, of which prospective cohort studies were found to be the most common. We investigated four primary outcomes (anxiety, depression, mood disorders, and stress-related disorders and several secondary outcomes of search. Seventy-nine percent of studies concerned depression, 42% anxiety, 29% mood disorders, and 21% stress-related disorders. Most of the studies showed a relationship between MMP and alterations in mental status. Nonetheless, the researchers usually evidenced only the co-occurrence of psychiatric disorders and dysfunctions of the masticatory muscles among the group of patients, in large part in women. Moreover, some studies were marked with limited generalizability of the reported results, quality flaws and heterogeneity. In the light of the analyzed literature, the causal relationship between mental states and MMP is still not clearly established.

  15. Assessment of prevalence study of 40 variables related to painful dysfunction syndrome of masticatory muscles in patients referred to faculty of dentistry in Mashhad, Northeast of Iran

    OpenAIRE

    2010-01-01

    Introduction: Painful dysfunction syndrome of masticatory muscles is one of the most important causes of pain in orofacial region. Therefore, the aim of this study was to evaluate the prevalency of 40 variables related to this disorder. Materials and Methods: A total 39 patients (32 females, 7 males) with painful dysfunction syndrome of masticatory muscles were studied. Patients were evaluated for prevalence of age, sex, job, marriage status, masticatory muscles tenderness, maximum mouth open...

  16. Effect of Progressive Muscle Relaxation on Pain Threshold and Effectiveness of Footballers’ Training

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    Jaworska Lilianna

    2015-12-01

    Full Text Available Purpose. Relaxing in the athlete’s training process is underutilized. Relaxation techniques, however, should be taught from the very beginning of the footballer’s training career. The main aim of this study was to present the effect of progressive muscle relaxation on pressure pain threshold levels and the effectiveness of the footballer’s training. Methods. A sample of 32 football players participated in the therapeutic program consisting of 8 PMR sessions. Before and after applying a pressure therapy, the pain threshold in the lumbar region was measured by a dolorimeter and the Cooper test was carried out to determine the footballers’ level of endurance. Results. PMR training did not increase significantly the pain threshold level in the experimental group (p > 0.05, but it increased significantly the distance covered in the Cooper test (p = 0.04. Analysis of the Spearman rank correlation was also carried out (p = 0.81. Conclusions. PMR does not lower pain perception threshold. PMR therapy increases the distance measured by the Cooper test. In order to determine the role of PMR in injury prevention, further research is necessary.

  17. Effect of physical training on function of chronically painful muscles: A randomized controlled trial

    DEFF Research Database (Denmark)

    Andersen, Lars L; Andersen, Christoffer H; Zebis, Mette K

    2008-01-01

    and electromyography (EMG) were recorded during maximal shoulder abductions in an isokinetic dynamometer at -60, 60, 0 and 180 degrees (.)s(-1). Further, a submaximal reference contraction with only the load of the arms was performed. Results: Significant changes were observed only in SST. Pain decreased 42-49% (P....01-0.05). While EMG activity of the unaffected deltoid remained unchanged during the maximal contractions, an increase in EMG amplitude (42-86%, P... during the reference contraction decreased significantly for both the trapezius and deltoid muscles (P

  18. Trunk muscle endurance and low back pain in female dance students.

    Science.gov (United States)

    Swain, Christopher; Redding, Emma

    2014-01-01

    Low back pain (LBP) is often cited as a common condition at all levels of dance. Evidence suggests that reduced endurance of the trunk muscles can predispose an individual to LBP. The purpose of this study was to examine differences in trunk muscle endurance in a sample of tertiary level dance students with and without LBP. Seventeen full-time female dance students were divided into two groups: dance students with LBP (N = 11), and without LBP (N = 6). All participants provided informed consent, and the study was approved by an institutional ethics review board. Participants performed four isometric tests that assess trunk muscle endurance: the right and left side plank, double straight leg raise (DSLR), and the Sorensen test. A modified version of the Osaka City University test was used to assess the presence of LBP. A significant difference (p well as the DSLR test, and students with LBP displayed lower levels of endurance compared to those without. No other significant differences were found. This study offers some evidence that reduced trunk muscle endurance is present among dancers with LBP and provides direction for future research into back health among dancers.

  19. Evaluation of efficacy and tolerability of eperisone and thiocolchicoside in treatment of low back pain associated with muscle spasm: An open label, prospective, randomized controlled trial

    Directory of Open Access Journals (Sweden)

    Syed H. Maaz

    2016-12-01

    Conclusions: Eperisone is an effective muscle relaxant with equivalent efficacy compared to Thiocolchicoside, and has a better tolerability in treatment of low back pain with muscle spasm. [Int J Basic Clin Pharmacol 2016; 5(6.000: 2669-2674

  20. Colon distention induces persistent visceral hypersensitivity by mechanotranscription of pain mediators in colonic smooth muscle cells.

    Science.gov (United States)

    Lin, You-Min; Fu, Yu; Wu, Chester C; Xu, Guang-Yin; Huang, Li-Yen; Shi, Xuan-Zheng

    2015-03-01

    Abdominal pain and distention are major complaints in irritable bowel syndrome. Abdominal distention is mainly attributed to intraluminal retention of gas or solid contents, which may cause mechanical stress to the gut wall. Visceral hypersensitivity (VHS) may account for abdominal pain. We sought to determine whether tonic colon distention causes persistent VHS and if so whether mechanical stress-induced expression (mechanotranscription) of pain mediators in colonic smooth muscle cells (SMCs) plays a role in VHS. Human colonic SMCs were isolated and stretched in vitro to investigate whether mechanical stress upregulates expression of the pain mediator cyclooxygenase-2 (COX-2). Rat colon was distended with a 5-cm-long balloon, and gene expression of COX-2, visceromotor response (VMR), and sensory neuron excitability were determined. Static stretch of colonic SMCs induced marked expression of COX-2 mRNA and protein in a force- and time-dependent manner. Subnoxious tonic distention of the distal colon at ∼30-40 mmHg for 20 or 40 min induced COX-2 expression and PGE2 production in colonic smooth muscle, but not in the mucosa layer. Lumen distention also increased VMR in a force- and time-dependent manner. The increase of VMR persisted for at least 3 days. Patch-clamp experiments showed that the excitability of colon projecting sensory neurons in the dorsal root ganglia was markedly augmented, 24 h after lumen distention. Administration of COX-2 inhibitor NS-398 partially but significantly attenuated distention-induced VHS. In conclusion, tonic lumen distention upregulates expression of COX-2 in colonic SMC, and COX-2 contributes to persistent VHS.

  1. Effect of the spacing of backpack shoulder straps on cervical muscle activity, acromion and scapular position, and upper trapezius pain.

    Science.gov (United States)

    Kim, Min-Hee; Yoo, Won-Gyu

    2013-06-01

    [Purpose] This study investigated the effect of the spacing of backpack shoulder straps on cervical muscle activity, acromion and scapular position, and upper trapezius (UT) pain. [Subjects] Fourteen males aged 20-32 years, were recruited. [Methods] We measured the MPS (midcervical paraspinal) activity, acromial angle, scapular distance, and UT pain after gait carrying a backpack with different shoulder strap spacings. [Results] The MPS, scapular inferior distance, and UT pressure pain threshold was significantly decreased and the acromion angle was significantly increased when carrying a backpack with wide shoulder straps compared to narrow shoulder straps. [Conclusion] A backpack with wide shoulder straps may cause scapular depression syndrome and chronic UT pain.

  2. EMG assessment of analgesia in treatment of posttonsillectomy pain: random allocation, preliminary report.

    Science.gov (United States)

    Vaiman, Michael; Krakovski, Daniel

    2012-02-01

    Surface electromyographic (sEMG) study of posttonsillectomy swallow-evoked muscular reactions was performed to assess validity of EMG in evaluation of analgesic drugs. Sixty randomly chosen operated adults were divided into group 1 (n=30) treated with oxycodone, and group 2 (n=30) treated with placebo. Pain assessment included visual analog scale (VAS) pain score and EMG data: the timing, electric amplitude, and graphic patterns of muscular activity. We investigated masseter, infrahyoid, and submental-submandibular muscles. Records from trapezius muscle were used for control. The results were compared with previously established normative database. The sEMG data were compared with VAS score. Oxycodone significantly reduced VAS pain score and changed muscle reactions to analgesia (amplitude) as was recorded by sEMG, whereas placebo reduced VAS pain score nonsignificantly and changed the reaction of the trapezius muscle only. Analgesia smoothes the recorded swallow peaks and increases time of deglutition. Statistically significant difference in muscle reactions was detected between the 2 groups. sEMG might be used for quantitative evaluation of analgesic drugs by assessment of muscular reactions to pain and to analgesia. This method might add quantitative justification to the information obtained by VAS pain testing and clinical data.

  3. Avaliação do dimorfismo sexual e da relação entre as características craniofaciais, dos arcos dentários e do músculo masseter na fase de dentição mista

    OpenAIRE

    Maria Carolina Salomé Marquezin; Annicele da Silva Andrade; Moara De Rossi; Gustavo Hauber Gameiro; Maria Beatriz Duarte Gavião; Paula Midori Castelo

    2014-01-01

    Purposeto evaluate sexual dimorphism and the relationship between craniofacial characteristics, dental arch morphology and masseter muscle thickness in children in the mixed dentition stage. Methodthe study sample comprised 32 children, aged 6-10 years (14♀/18♂) with normal occlusion. Craniofacial characteristics, dental morphology and masseter muscle thickness were evaluated by means of posteroanterior cephalometric radiographs, dental cast evaluation and ultrasound exam, respectively. The r...

  4. Craniofacial Pain: Brainstem Mechanisms

    Directory of Open Access Journals (Sweden)

    Barry J Sessle

    1996-01-01

    Full Text Available This article reviews recent research advances in animals that have identified critical neural elements in the brainstem receiving and transmitting craniofacial nociceptive inputs, as well as some of the mechanisms involved in the modulation and plasticity of nociceptive transmission. Nociceptive neurones in the trigeminal (V brainstem sensory nuclear complex can be classified as nociceptive-specific (NS or wide dynamic range (WDR. Some of these neurones respond exclusively to sensory inputs evoked by stimulation of facial skin or oral mucosa and have features suggesting that they are critical neural elements involved in the ability to localize an acute superficial pain and sense its intensity and duration. Many of the V brainstem nociceptive neurones, however, receive convergent inputs from afferents supplying deep craniofacial tissues (eg, dural vessel, muscle and skin or mucosa. These neurones are likely involved in deep pain, including headache, because few nociceptive neurones receive inputs exclusively from afferents supplying these tissues. These extensive convergent input patterns also appear to be important factors in pain spread and referral, and in central mechanisms underlying neuroplastic changes in V neuronal properties that may occur with injury and inflammation. For example, application of the small fibre excitant and inflammatory irritant mustard oil into the temporomandibular joint, masseter or tongue musculature induces a prolonged but reversible enhancement of responses to cutaneous and deep afferent inputs of most WDR and NS neurones. These effects may be accompanied by increased electromyographic activity reflexly induced in the masticatory muscles by mustard oil, and involve endogenous N-methyl-D-aspartate and opioid neurochemical mechanisms. Such peripherally induced modulation of brainstem nociceptive neuronal properties reflects the functional plasticity of the central V system, and may be involved in the development of

  5. The Comparison of the Effects of Trigger Points Pressure Release and Kinesio Taping on Pain and Hip Abductor Muscles Strength in Patients with Patellofemoral Pain Syndrome

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    Vahid Mazloum

    2016-10-01

    Full Text Available Background & objectives: Hip muscles insufficiency plays a significant role in deterioration of patellofemoral pain syndrome (PFPS, which can be manifested as myofascial trigger point (MTrPs in hip muscles. Then, our purpose was to determine the prevalence of MTrPs in the gluteus medius (GMe and quadratus lumborum (QL muscles and to investigate the effect of a therapeutic intervention on pain intensity and hip abductor muscles isometric strength in patients with PFPS. Methods: Forty volunteer subjects (20 patients and 20 healthy participated in the study. Latent MTrPs in GMe and QL were evaluated and a handheld dynamometer was used to measure peak isometric strength test (PIST for hip abductors. Patients with PFPS having MTrPs in GMe were randomly divided into either a treatment group (Mean age±SD: 23.2±4.3 years or control (Mean age±SD: 24.4±4.6 years. The therapeutic intervention included trigger point pressure release (TrPPR and Kinesio Taping® (KT. Pain intensity and PIST for hip abductors were assessed at baseline and after intervention in both groups. Results: There is more significant patients with PFPS having latent MTrPs in GMe and QL than the healthy counterparts (p0.05. Conclusion: Concomitant using of TrPPR therapy and KT method can decrease pain intensity in individuals with PFPS. Further studies are required to understand the underlying mechanisms.

  6. Effect of progressive muscle relaxation therapy on improving signs and symptoms of patients with myofacial pain dysfunction syndrome

    Directory of Open Access Journals (Sweden)

    Momen Beitollahi J.

    2009-03-01

    Full Text Available "nBackground and Aim: One of the most common causes of facial pain, is muscular pain. MPDS is one of the most important disorders of facial area that many of patients suffer from pain, tenderness of one or more masticatory muscles and limitation of movement. Psychological factors play an important role in MPDS. Anxiety and depression by increasing muscle tension, can cause myofacial pain syndrome; They can also accompany the syndrome as comorbidities or develop as sequelae of chronic pain and disability. Many approaches can be used to treat myofacial pain syndrome. The least invasive and least traumatic approach should be se.lected. Often, treatment for myofacial pain syndrome fails, because underlying problems go untreated. Progressive Muscle Relaxation (PMR is mainly used for treating anxiety and depression. The aim of this study was to evaluate the effect of PMR in improving signs and symptoms of patients with MPDS. "nMaterials and Methods: In this before and after clinical trial study, 33 patients with MPDS that had anxiety and or mild depression(were assessed by Beck Inventorywere treated by PMR in a period of a month (3 visitsand were followed up until 2 months. Analysis was done using paired t-test/ wilcoxon-sign-rank test. "nResults: The results of this study showed that variants like intensity of pain, tenderness of masticatory muscles, maximum opening of mouth with and without pain, anxiety (p<0.001 and depression (p=0.001 improved significant 16 after treatment in comparison with before treatment. "nConclusion: In conclusion, PMR is effective in improving signs and symptoms in patients with MPDS. Therefore psychological status should be considered in treatment plan of these patients.

  7. Comparison of the effects of knee and hip and single knee muscles strengthening/ stretching exercises on pain intensity and function in athletes with patellofemoral pain syndrome

    Directory of Open Access Journals (Sweden)

    Vahid Mazloum

    2016-08-01

    Full Text Available Background: Patellofemoral pain syndrome (PFPS is a common musculoskeletal condition among athletes. The evidence emphasizes on the importance of hip musculature strengthening exercises for such patients. Objective: To investigate the effects of strengthening-stretching knee muscles exercises and hip posterolateral musculature exercises in athletes with PFPS. Methods: In this clinical trial, 28 athletes with age average of 22.7±2.4 years with PFPS were allocated into conventional knee muscles exercises (CKME (n=14 and posterolateral hip muscles exercises (PHME (n=14. The subjects of both groups performed the supervised exercise protocols in 12 sessions. The Visual Analogue Scale and 6-minute walking tests were administrated respectively to evaluate pain intensity and function. The data were analyzed using Shapiro-wilk test, Independent-sample t test, and Repeated Measure ANOVA test. Findings: Demographic, pain intensity, and physical function data were similar between groups at baseline. Both groups significantly improved in pain intensity and function following a 4-week exercise program. Additionally, the athletes in PHME group had higher level of decreased pain intensity and improved function in follow-up assessment than the subjects in CKME group. Conclusion: Using hip posterolateral musculature exercises in addition to the knee conventional exercises is more effective for athletes with PFPS.

  8. Myoelectric manifestations of jaw elevator muscle fatigue and recovery in healthy and TMD subjects.

    Science.gov (United States)

    Castroflorio, T; Falla, D; Tartaglia, G M; Sforza, C; Deregibus, A

    2012-09-01

    The effects of muscle pain and fatigue on the control of jaw elevator muscles are not well known. Furthermore, the myoelectric manifestations of fatigue and recovery from fatigue in the masticatory muscles are not reported in literature. The main aims of this study were (i) to evaluate the possible use of surface electromyography (sEMG) as an objective measure of fatigue of the jaw elevator muscles, (ii) to compare the myoelectric manifestations of fatigue in the temporalis anterior and masseter muscles bilaterally, (iii) to assess recovery of the investigated muscles after an endurance test and (iv) to compare fatigue and recovery of the jaw elevator muscles in healthy subjects and patients with muscle-related temporomandibular disorders (TMD). The study was performed on twenty healthy volunteers and eighteen patients with muscle-related TMD. An intra-oral compressive-force sensor was used to measure the voluntary contraction forces close to the intercuspal position and to provide visual feedback of submaximal forces to the subject. Surface EMG signals were recorded with linear electrode arrays during isometric contractions at 20%, 40%, 60% and 80% of the maximum voluntary contraction force, during an endurance test and during the recovery phase. The results showed that (i) the slope of the mean power spectral frequency (MNF) and the initial average rectified value (ARV) could be used to monitor fatigue of the jaw elevators, (ii) the temporalis anterior and masseter muscle show the same myoelectric manifestations of fatigue and recovery and (iii) the initial values of MNF and ARV were lower in patients with muscle-related TMD. The assessment of myoelectric manifestations of fatigue in the masticatory muscles may assist in the clinical assessment of TMDs.

  9. Skeletal Muscle Haemangioma: A Cause for Chronic Pain about the Knee: A Case Report

    Directory of Open Access Journals (Sweden)

    Kopuri Ravi Kiran

    2012-01-01

    Full Text Available Skeletal muscle haemangiomas are uncommon soft tissue tumors; more than 90% are misdiagnosed initially. They present as chronic pain and swelling in a muscle with or without a history of trauma. Plain X-rays, bone scans, computerized tomography (CT studies, and angiography studies may not always be specific for this tumor. Diagnostic ultrasound is an appropriate initial imaging modality for suspected haemangioma, although magnetic resonance imaging is the investigation of choice. Many treatment modalities for the symptomatic haemangiomas are available of which surgical excision is the most preferred. We present an unusual case of pain, swelling, and restriction of movements in the right knee following an episode of trauma in a 12-year-old boy who was being followed for 1 year by a general practioner and later referred to us. The patient was diagnosed to have intramuscular cavernous haemangioma in the vastus medialis by us for which he was treated by surgical excision and followed for 1 year and found to have no recurrence. The clinical features, radiological picture, pathological histology, diagnostic tools, and treatment options have been discussed.

  10. Specific proteins of the trapezius muscle correlate with pain intensity and sensitivity – an explorative multivariate proteomic study of the trapezius muscle in women with chronic widespread pain

    Directory of Open Access Journals (Sweden)

    Olausson P

    2016-06-01

    Full Text Available Patrik Olausson, Bijar Ghafouri, Nazdar Ghafouri, Björn Gerdle Pain and Rehabilitation Centre, Department of Medical and Health Sciences, Linköping University, Linköping, Sweden Abstract: Chronic widespread pain (CWP including fibromyalgia syndrome (FMS has a high prevalence and is associated with prominent negative consequences. CWP/FMS exhibits morphological and functional alterations in the central nervous system. The importance of peripheral factors for maintaining the central alterations are under debate. In this study, the proteins from biopsies of the trapezius muscle from 18 female CWP/FMS patients and 19 healthy female controls were analyzed. Pain intensity and pressure pain thresholds (PPT over the trapezius muscles were registered. Twelve proteins representing five different groups of proteins were important regressors of pain intensity in CWP/FMS (R2=0.99; P<0.001. In the regression of PPT in CWP/FMS, it was found that 16 proteins representing six groups of proteins were significant regressors (R2=0.95, P<0.05. Many of the important proteins were stress and inflammation proteins, enzymes involved in metabolic pathways, and proteins associated with muscle damage, myopathies, and muscle recovery. The altered expression of these proteins may reflect both direct and indirect nociceptive/inflammatory processes as well as secondary changes. The relative importance of the identified proteins and central alterations in CWP need to be investigated in future research. Data from this and the previous study concerning the same cohorts give support to the suggestion that peripheral factors are of importance for maintaining pain aspects in CWP/FMS. Keywords: chronic widespread pain, proteomics, biomarkers, multivariate data analysis, pain threshold, numeric rating scale

  11. Muscle Disorders

    Science.gov (United States)

    Your muscles help you move and help your body work. Different types of muscles have different jobs. There are many problems that can affect muscles. Muscle disorders can cause weakness, pain or even ...

  12. The effects of stabilization exercise on pain, functional disability and muscle endurance in patients suspectedto lumbar segmental instability

    Directory of Open Access Journals (Sweden)

    Y. Javadian

    2008-01-01

    Full Text Available AbstractIntroduction: Lumbar segmental instability is one of the subgroups of non specific chronic low back pain and it seems that 30-40% of patients with LBP suffer from lumbar segmental instability. Pain intensity, functional disability and reduced muscle endurance are common in such patients. The aim of this study was to evaluate the effects of stabilization exercise on pain, functional disability and muscle endurance in patients suspected to lumbar segmental instability Material & methods: Following ethical approval, a randomized clinical trial was carried out on 30 patients suspected to lumbar segmental instability ranging from 18-45 years old. They were randomly divided into two groups; the first group underwent routine exercise only while the second group performed routine exercise plus stabilization training for 8 weeks. Outcome measure included pain intensity, functional disability, and flexion and extension range of motion and flexor, extensor and side support muscle endurance which were evaluated before and after treatment. Data were analyzed using paired t test and independent t test.Results: Muscle endurance and flexion range of motion increased in both groups although the increase was higher in stabilization training group (p=0.00. Pain intensity and functional disability significantly decreased in both groups (p=0.00, but decreasing of pain intensity and functional disability were more in stabilization training group (p=0.00. Conclusion: Stabilization training is more effective than routine exercise in improvement of pain intensity, functional disability, muscle endurance and range of motion in patients suspected to lumbar segmental instability. J Mazand Univ Med Sci 2008; 18(65: 63-73 (Persian

  13. Local and Systemic Changes in Pain Sensitivity After 4 Weeks of Calf Muscle Stretching in a Nonpainful Population

    DEFF Research Database (Denmark)

    Bartholdy, Cecilie; Zangger, Graziella; Hansen, Lisbeth

    2016-01-01

    BACKGROUND: Stretching is often used in clinical practice for a variety of purposes, including pain therapy. The possible mechanism behind the effect of stretching remains to be clarified. AIM: To investigate whether 4 weeks of unilateral stretching of the calf muscles would affect local...... and central pain sensitivity. METHOD: This study was a randomized assessor-blinded clinical study. Healthy participants (age 18 to 40) were included and randomized. Participants in the intervention group were instructed to perform 2 stretching exercises targeting the calf muscles; 3 times 30 seconds, 7 days...... a week for 4 weeks on the dominant leg. Participants in the control group were instructed not to do any stretching for 4 weeks. Pressure pain threshold (PPT) and temporal summation (TS) of pressure pain were measured on the stretched calf, the contra-lateral calf, and contra-lateral lower arm using...

  14. Differences in cervical multifidus muscle thickness during isometric contraction of shoulder muscles: a comparison between patients with chronic neck pain and healthy controls.

    Science.gov (United States)

    Rahnama, Leila; Rezasoltani, Asghar; Zavieh, Minoo Khalkhali; NooriKochi, Farhang; Baghban, Alireza Akbarzadeh

    2015-01-01

    The purposes of this study were to (1) measure the thickness of cervical multifidus muscle (CMM) in different maximal voluntary contraction percentages of isometric contraction of shoulder muscles, (2) evaluate the differences of the CMM thickness in different directions of the shoulder movement, and (3) compare the changes in the CMM thickness of participants with neck pain and also of healthy individuals. Twenty healthy men (age, 27.45 ± 4.37 years; height, 177 ± 4.66 cm; weight, 72.85 ± 6.46 kg) and 20 men with chronic mechanical neck pain (age, 28.90 ± 5.53 years; height, 176 ± 5.98 cm; weight, 73.15 ± 7.82 kg) participated in the study. Both the right and left CMM thicknesses were measured using an ultrasound device while participants performed isometric contraction of shoulder muscles in 6 movement directions. In both groups, an increment of CMM thickness followed as the increase of isometric force (P muscle thickness of healthy participants was substantially more than the chronic mechanical neck pain participants (P = .03). Although no significant difference of CMM thickness was seen among the effects of the 6 force directions (P > .05), there was a significant difference of activity noted between the left and right sides (P = .047). The results of the present study indicate that isometric contraction of shoulder muscles caused an increase in the CMM thickness regardless of force direction. This increase was seen in both groups of healthy participants and patients with neck pain. However, less thickness changes were observed in participants with neck pain, which may be interpreted as reduced CMM activity in such people. Copyright © 2015 National University of Health Sciences. Published by Elsevier Inc. All rights reserved.

  15. Evolution of Muscles Dysfunction From Myofascial Pain Syndrome Through Cervical Disc-Root Conflict to Degenerative Spine Disease.

    Science.gov (United States)

    Lisiński, Przemysław; Huber, Juliusz

    2017-02-01

    Comparative clinical and neurophysiological study in three groups of patients with general diagnosis of neck pain. To determine symptoms of muscles dysfunction in patients with myofascial pain syndrome, disc-root conflict, and degenerative changes at cervical spine. The explanation for cervical pain origin should be based on results from chosen clinical and neurophysiological studies in correlation with neuroimaging findings. Three subgroups of patients (N = 60 each) with certain symptoms were examined. Clinical evaluation included examination of pain intensity in VAS scale, muscle strength in Lovett scale, evaluation of reflexes, Spurling test, assessment of active trigger points (TRPs), and superficial sensory perception. Neurophysiological testing included surface electromyography at rest (rEMG) and during maximal contraction (mcEMG) as well as electroneurography (ENG). The greatest pain intensity with its decentralization phenomenon occurred in patients with disc-root conflict. Significant decrease of muscle strength was detected in trapezius muscle in myofascial pain syndrome subgroup. Weakness of abductor pollicis brevis muscle in patients with disc-root conflict differed them from patients with myofascial pain syndrome (P = 0.05). Patients with disc-root conflict and degenerative spine disease showed differences (P = 0.03) in reflexes evoked from triceps brachii. Positive Spurling symptom was most common (56.7%) in disc-root conflict subgroup. TRPs in trapezius muscle were found in all patients with myofascial pain syndrome. Results of rEMG amplitude measurements differed patients at P = 0.05. Only mcEMG recording from abductor pollicis brevis muscle allows for their clear cut differentiation. ENG studies showed abnormalities in patients with disc-root conflict and degenerative spine disease (P from 0.05 to 0.02). Positive correlation of VAS, TRPs, and rEMG as well as Lovett scores, mcEMG, and ENG results was found. Only applying several

  16. Comparison of clinical efficacy between radiofrequency ablation and botulinum toxin type A in treatment of benign masseter hypertrophy%射频消融与A型肉毒毒素治疗咬肌良性肥大的临床效果比较

    Institute of Scientific and Technical Information of China (English)

    陈刚; 黄金龙; 张骏; 刘育凤; 闻可; 刘宁; 王金明

    2015-01-01

    Objective To evaluate masseter thickness and its complications of radiofrequency ablation and botulinum toxin type A in the treatment of masseter hypertrophy.Methods Totally 36 patients of benign masseter hypertrophy were randomly divided into radiofrequency ablation therapy group (18 patients) and the injection of botulinum toxin type A treatment group (18 patients).The thickness of the masseter and complications were analyzed before treatment,6 months and 12 months after treatment.Results The average thickness of masseter muscle in botulinum toxin type A and radiofrequency ablation groups was significantly reduced 6 or 12 months after treatment,and the difference was statistically significant (P<0.05).However,the thickness of masseter muscle in radiofrequency ablation group after 12 months reduced greater than that in botulinum toxin type A group (P<0.05).Complications of botulinum toxin type A group were swallow difficulty (one patient),unnatural facial expressions (4 patients) and pain at injection site (10 patients) and that in radiofrequency ablation treatment group were that 18 patients had swelling of the skin 1 to 2 weeks after treatment.All patients had recovery 2 weeks after treatment.There was no facial nerve,parotid duct injury,or oral dysfunction.Conclusions The lasting effect of radiofrequency ablation treatment for benign masseter hypertrophy is longer than that of botulinum toxin type A.%目的 比较射频消融和A型肉毒毒素注射治疗咬肌肥大的临床效果.方法 将36例咬肌良性肥大的患者按照治疗方法不同完全随机分为接受射频消融治疗组和注射A型肉毒毒素治疗组,每组18例.评价治疗前、治疗后6个月、12个月时咬肌的厚度及并发症.结果 A型肉毒杆菌毒素治疗组中,与治疗前相比,右侧或左侧平均咬肌厚度治疗后6、12个月明显减少,差异有统计学意义(P<0.05).射频消融治疗组中,与治疗前相比,治疗后6、12个月咬

  17. Effect of duration of smartphone use on muscle fatigue and pain caused by forward head posture in adults

    OpenAIRE

    2016-01-01

    [Purpose] The effect of duration of smartphone use on neck and shoulder muscle fatigue and pain was investigated in adults with forward head posture. [Subjects and Methods] Thirty-four adults with forward head posture were classified into groups by duration of smartphone use: 11 used a smartphone for 10 minutes each (group 1), 12 for 20 minutes each (group 2), and 11 for 30 minutes each (group 3). Fatigue cervical erector spinae and upper trapezius muscles was measured by electromyography, an...

  18. Chronic Pain in Children and Adolescents: Diagnosis and Treatment of Primary Pain Disorders in Head, Abdomen, Muscles and Joints.

    Science.gov (United States)

    Friedrichsdorf, Stefan J; Giordano, James; Desai Dakoji, Kavita; Warmuth, Andrew; Daughtry, Cyndee; Schulz, Craig A

    2016-12-10

    Primary pain disorders (formerly "functional pain syndromes") are common, under-diagnosed and under-treated in children and teenagers. This manuscript reviews key aspects which support understanding the development of pediatric chronic pain, points to the current pediatric chronic pain terminology, addresses effective treatment strategies, and discusses the evidence-based use of pharmacology. Common symptoms of an underlying pain vulnerability present in the three most common chronic pain disorders in pediatrics: primary headaches, centrally mediated abdominal pain syndromes, and/or chronic/recurrent musculoskeletal and joint pain. A significant number of children with repeated acute nociceptive pain episodes develop chronic pain in addition to or as a result of their underlying medical condition "chronic-on-acute pain." We provide description of the structure and process of our interdisciplinary, rehabilitative pain clinic in Minneapolis, Minnesota, USA with accompanying data in the treatment of chronic pain symptoms that persist beyond the expected time of healing. An interdisciplinary approach combining (1) rehabilitation; (2) integrative medicine/active mind-body techniques; (3) psychology; and (4) normalizing daily school attendance, sports, social life and sleep will be presented. As a result of restored function, pain improves and commonly resolves. Opioids are not indicated for primary pain disorders, and other medications, with few exceptions, are usually not first-line therapy.

  19. Chronic Pain in Children and Adolescents: Diagnosis and Treatment of Primary Pain Disorders in Head, Abdomen, Muscles and Joints

    Directory of Open Access Journals (Sweden)

    Stefan J. Friedrichsdorf

    2016-12-01

    Full Text Available Primary pain disorders (formerly “functional pain syndromes” are common, under-diagnosed and under-treated in children and teenagers. This manuscript reviews key aspects which support understanding the development of pediatric chronic pain, points to the current pediatric chronic pain terminology, addresses effective treatment strategies, and discusses the evidence-based use of pharmacology. Common symptoms of an underlying pain vulnerability present in the three most common chronic pain disorders in pediatrics: primary headaches, centrally mediated abdominal pain syndromes, and/or chronic/recurrent musculoskeletal and joint pain. A significant number of children with repeated acute nociceptive pain episodes develop chronic pain in addition to or as a result of their underlying medical condition “chronic-on-acute pain.” We provide description of the structure and process of our interdisciplinary, rehabilitative pain clinic in Minneapolis, Minnesota, USA with accompanying data in the treatment of chronic pain symptoms that persist beyond the expected time of healing. An interdisciplinary approach combining (1 rehabilitation; (2 integrative medicine/active mind-body techniques; (3 psychology; and (4 normalizing daily school attendance, sports, social life and sleep will be presented. As a result of restored function, pain improves and commonly resolves. Opioids are not indicated for primary pain disorders, and other medications, with few exceptions, are usually not first-line therapy.

  20. The response of cortical alpha activity to pain and neuromuscular changes caused by exercise-induced muscle damage.

    Science.gov (United States)

    Plattner, K; Lambert, M I; Tam, N; Baumeister, J

    2014-02-01

    Exercise-induced muscle damage (EIMD) is characterized by pain, swelling, and shortening of the muscle; increased serum creatine kinase; decreased force output; and altered neuromuscular function. The aim of this study was to investigate the effects of EIMD to determine the relationship between the peripheral symptoms, neuromuscular changes, and delayed pain sensation during a submaximal movement of the biceps brachii on cortical alpha (α) activity. In contrast to the control (n = 12) group, the experimental (n = 16) group participated in an EIMD protocol, and both groups were monitored for 132 h post-EIMD protocol. At 12 h, neuromuscular functioning was already disturbed while the sensation of pain was perceived, but not fully developed. Muscle pain scores in the experimental group peaked after 36 h with the lowest torque reported at 12 h. α-1 activity increased significantly in the motor and somatosensory area 12 h post-EIMD while α-2 activity increased in the contralateral fronto-central area. At 36 h, pain had further increased and neuromuscular function improved while α-1 and α-2 activities had decreased. We hypothesize that α-1 activity over the motor and somatosensory cortex of the experimental group displays a compensatory increase in response to the changes in neuromuscular function during movement, while an increase in α-2 activity is related to the suppression of pain experienced within the first 12 h.

  1. Skeletal muscle contractility, self-reported pain and tissue sensitivity in females with neck/shoulder pain and upper Trapezius myofascial trigger points - a randomized intervention study

    DEFF Research Database (Denmark)

    Myburgh, Corrie; Hartvigsen, Jan; Aagaard, Per

    2012-01-01

    -intervention and 48 hours post-intervention. Symptomatic and asymptomatic participant groups were each randomized into two treatment sub-groups (superficial (SDN) and deep dry needling (DDN)) after baseline testing. At 48 hours post-intervention participants were asked whether delayed onset muscle soreness (DOMS) and....../or post-needling soreness had developed. RESULTS: Muscle contractile characteristics did not differ between groups at baseline. Forty-six individuals developed muscle soreness (39 from mechanical testing and seven from needling). No inter-group differences were observed post-intervention for Fmax or RFD......The present investigation is one of the first to examine the hypothesis of gross muscle contractile inhibition due to the presence of diagnostically relevant MFTrPs.Individuals suffering from clinically relevant levels of self-reported pain are able to tolerate maximum voluntary contraction testing...

  2. Peripheral nerve stimulation (PNS) in the trapezius muscle region alleviate chronic neuropathic pain after lower brachial plexus root avulsion lesion: A case report

    DEFF Research Database (Denmark)

    Sørensen, Jens Christian Hedemann; Meier, Kaare; Perinpam, Larshan;

    Peripheral nerve stimulation (PNS) in the trapezius muscle region alleviate chronic neuropathic pain after lower brachial plexus root avulsion lesion: A case report......Peripheral nerve stimulation (PNS) in the trapezius muscle region alleviate chronic neuropathic pain after lower brachial plexus root avulsion lesion: A case report...

  3. Effects of Low-level Laser in the Treatment of Myofascial Pain Dysfunction Syndrome

    Science.gov (United States)

    Azizi, Arash; Sahebjamee, Mahnaz; Lawaf, Shirin; Jamalee, Fereydoon; Maroofi, Nader

    2007-01-01

    Background and aims Muscular pain in the facial region is the most common cause of facial pains. Myofascial pain dysfunction syndrome (MPDS) is one of the most important facial muscle disorders comprising of signs and symptoms including pain during function, tenderness in the muscles of mastication and restricted jaw movement. Due to the lack of an accepted therapeutic approach, the purpose of this paper was to find an effective treatment to decrease the pain of such patients. Considering the analgesic and anti-inflammatory action of laser therapy, the effects of low level laser (Ga-Al-As) in the treatment of MPDS patients referred to Tehran University of Medical Sciences Faculty of Dentistry, were investigated in the present study. Materials and methods This study was a quasi-experimental research. Twenty-two MPDS patients were selected from those referred to Department of Oral Medicine, Tehran University of Medical Sciences Faculty of Dentistry. Clinical examination was performed at six stages in the following order: prior to the treatment, at 2 and 4 weeks after treatment, and monthly thereafter for a 3-months follow-up. All patients underwent low-level laser therapy for 4 weeks (12 sessions). Variables such as pain severity, pain of cheek region, pain frequency, tenderness of masticatory muscles, click, and mouth opening were evaluated at each stage. Numerical variables were investigated using Analysis of Variance test for repeated measures whereas ranking variables were studied by non-parametric Kruskal-Wallis test. Results At the end of treatment period, pain severity, pain of cheek region, pain frequency, tenderness of masseter, temporalis, medial pterygoid, and lateral pterygoid muscles showed significant improvement as compared with the commencement of any treatment which continued during the 3-months post-treatment (ppain and decrease the tenderness of masticatory muscles among MPDS patients through a continuous and regular therapeutic program. PMID

  4. Decreased task duration and unchanged trunk muscle activity in low-back pain patients during stair climbing after back extensor muscle fatigue

    DEFF Research Database (Denmark)

    Larsen, Lars Henrik; Østergaard, Gert Værge; Brogner, Heidi Marie

    2014-01-01

    Low-back pain (LBP) is a major problem. Spine control and stability mechanisms are important but the knowledge of these parameters in functions is sparse. 7 healthy / 5 recurrent mild-to-moderate LBP patients participated in assessment of abdominal, lumbar and gluteal muscles' surface EMG and video......- and abdominal muscle activity in healthy than in patients in most phases, but during descend transfer patients activity decreased. In LBP patients back extensor fatigue resulted in decreased muscular activity in the trunk muscles during stair stepping compared to healthy. Decreased duration of the motor tasks...... recording during 10 concurrent stair steps pre / post lumbar extensor muscle exhaustion. Duration of gait tasks were shorter in LBP patients generally and longer during load and shorter during transfer in descend stepping after back extensor fatigue. Back extensor fatigue resulted in higher back...

  5. Referred Pain Patterns of the Infraspinatus Muscle Elicited by Deep Dry Needling and Manual Palpation.

    Science.gov (United States)

    Poveda-Pagán, Emilio J; Lozano-Quijada, Carlos; Segura-Heras, Jose V; Peral-Berna, María; Lumbreras, Blanca

    2017-03-07

    To identify the most common referred pain (ReP) pattern of the infraspinatus myofascial trigger point (MTrP) and compare its coincidence with the original ReP pattern, to verify whether there are any significant differences by sex and types of technique and to determine the observed signs and symptoms evoked by deep dry needling (DDN) and manual palpation (MPal). A cohort study of patients randomized to two different examination methods (July and August 2016). Students and staff recruited from Miguel Hernandez University (Southeast Spain). One hundred thirty-three participants (70.7% women) with shoulder complaints were randomly assigned to either an MPal (n = 67) or DDN group (n = 66). The same physiotherapist carried out the techniques on all participants, and the same protocol was followed for both the DDN and MPal groups. The physiotherapist did not ask participants about their pain features or other relevant issues. Local twitch response (LTR) and ReP assessed through a visual analogue scale and features of ReP of the infraspinatus muscle. The areas with the highest percentage of ReP were the front (area 3; 27.1%) and back (area 11; 21.1%) of the arm, anterior (area 4; 36.1%) and posterior (area 12; 42.1%) shoulder, and infraspinatus muscle area. DDN proved to be significantly easier than MPal in evoking an LTR (p ≤ 0.001). There were significant differences between sexes in zone 2 (p = 0.041) and no statistically significant differences were found by technique. The ReP pattern of the infraspinatus muscle coincides with the original pattern described by Travell and Simons, although the neck area should be questioned. The study found no significant differences in the ReP pattern by sex and when comparing MPal with DDN of MTrP of the infraspinatus muscle. DDN proved to be significantly easier than MPal in evoking an LTR.

  6. Association between changes in electromyographic signal amplitude and abdominal muscle thickness in individuals with and without lumbopelvic pain.

    Science.gov (United States)

    Whittaker, Jackie L; McLean, Linda; Hodder, Joanne; Warner, Martin B; Stokes, Maria J

    2013-01-01

    Validation study. To investigate the association between changes in electromyographic (EMG) signal amplitude and sonographic measures of muscle thickness of 4 abdominal muscles, during 2 clinical tests, in adults with and without lumbopelvic pain. There is a trend in rehabilitation to use ultrasound imaging (USI) to determine the extent of abdominal muscle contraction. However, the literature investigating the relationship between abdominal muscle thickness change and level of activation is inconclusive and has not included clinically relevant tasks. Simultaneous recording from fine-wire EMG and USI was performed for 4 abdominal muscles, in 7 adults with lumbopelvic pain (mean ± SD age, 29.7 ± 12.0 years) and 7 adults without lumbopelvic pain (32.0 ± 10.6 years), during an active straight leg raise (ASLR) test and an abdominal drawing-in maneuver (ADIM). Cross-correlation functions and linear regression analyses were used to describe the relationship between the 2 measures. Analyses of variance were used to compare individuals with and without lumbopelvic pain, with an alpha set at .05. Across all muscles, peak cross-correlation values were low (ASLR, r = 0.28 ± 0.09; ADIM, r = 0.35 ± 0.11), and there was large variability in associated time lags (ASLR, τ = 0.69 ± 2.56 seconds; ADIM, τ = 0.53 ± 3.75 seconds). Regression analyses did not detect a systematic pattern of association between EMG signal amplitude and USI measurements, and analyses of variance revealed no differences between cohorts. These results suggest a weak relationship between EMG amplitude and abdominal muscle thickness change measured with USI during the ADIM and ASLR, and raise questions about thickness change derived from USI as a measure of muscular activity for the abdominal musculature.

  7. Effects of individual strengthening exercises for the stabilization muscles on the nutation torque of the sacroiliac joint in a sedentary worker with nonspecific sacroiliac joint pain.

    Science.gov (United States)

    Yoo, Won-Gyu

    2015-01-01

    [Purpose] We investigated the effects of individual strengthening exercises for the stabilization muscles on the nutation torque of the sacroiliac joint in a sedentary worker with nonspecific sacroiliac joint pain. [Subject] A 36-year-old female complained of pain in the sacroiliac joints. [Methods] The subject performed individual strengthening exercises for the stabilization muscles for nutation torque of the sacroiliac joint for 3 weeks. Pain-provocation tests and visual analog scale (VAS) scores were evaluated before and after the exercises. [Results] After performing the individual strengthening exercises for the erector spinae, rectus abdominis, and biceps femoris muscles for 3 weeks, the subject displayed no pain in the pain provocation tests, and the VAS score was 2/10. [Conclusion] The individual strengthening exercises for the stabilization muscles of the sacroiliac joint performed in the present study appear to be effective for sedentary workers with sacroiliac joint pain.

  8. The effects of low level laser therapy (Ga- Al- As on myofascial pain dysfunction syndrome

    Directory of Open Access Journals (Sweden)

    Sahebjamei M

    2002-06-01

    Full Text Available Muscular pain is one of the most common causes for facial pain. Myofacial pain dysfunction"nsyndrome (MPDS is one of the most important disorders of facial area that affected patients suffer from"npain, tenderness of one or more masticatory muscles and limitation of movements. Lack of specific and"neffective therapeutic method, makes it necessary to find a treatment to decrease pain. Considering the"nanalgesic and anti- inflammatory effects of low-level laser, some investigators have recommended it for"nMPDS patient's treatment. In this study, the effects of low level laser (Ga-Al-As on MPDS patients"nreferred to dental faculty of Tehran University of Medical Sciences, were investigated. Twenty- two"nMPDS patents, with mean age 33.32 years, were treated for 4 weeks (12 visits. Clinical examinations"nwere performed in 6 stages. The results of this study showed that variables such as pain severity, cheek"npain, pain frequency and tenderness of masseter, temporal, internal and external pterygoid muscles, had a"nstatistically significant improvement at the end of treatment with low level laser (GA-A1-AS which"nlasted for three months, (follow- up period. Results of this study showed that, low-level laser therapy"nhas a sedative effect on the pain and tenderness of masticatory muscles in MPDS. Patients and having an"naccurate and regular program to complete treatment period, has an important role in MPDS"nimprovement.

  9. Flexion Relaxation Ratio Not Responsive to Acutely Induced Low Back Pain from a Delayed Onset Muscle Soreness Protocol

    Science.gov (United States)

    Horn, Maggie E.; Bishop, Mark D.

    2013-01-01

    Background. The flexion relaxation ratio (FRR) has been suggested as a measure of muscular performance in patients with low back pain (LBP). The purpose of this study was to investigate whether the FRR was responsive to acute LBP produced from a delayed onset muscle soreness (DOMS) protocol. Methods. Fifty-one pain-free volunteers performed DOMS to induce LBP. Current pain intensity, trunk flexion range of motion (ROM), and passive straight leg raise (SLR) were measured at baseline, 24 and 48 hours after DOMS. Participants were categorized into pain groups based on reported current pain intensity. Changes in FRR, trunk flexion ROM, and SLR ROM were examined using two-way repeated measures analysis of variance. Results. Pain group was not found to have a significant effect on FRR (F1,29 = 0.054, P = 0.818), nor were there any two-way interactions for changes in FRR. The pain group had decreased trunk flexion ROM compared to the minimal pain group (F1,38 = 7.21, P = 0.011), but no decreases in SLR ROM (F1,38 = 3.51, P = 0.057) over time. Interpretation. There were no differences in FRR based on reported pain intensity of LBP from a DOMS protocol. The responsiveness of FRR might be limited in patients with acute onset LBP of muscular origin. PMID:27335879

  10. Kinesiotherapy for quality of life, pain and muscle strength of rheumatoid arthritis and systemic lupus erythematosus patient. Case report

    OpenAIRE

    Myra,Rafaela Simon; DeMarco,Mariângela; Zanin, Caroline; Wibelinger, Lia Mara

    2015-01-01

    ABSTRACT BACKGROUND AND OBJECTIVES: Rheumatoid arthritis is an inflammatory, chronic and progressive disease. It impairs joint synovial membranes and may induce bone and cartilage destruction. Many diseases may follow rheumatoid arthritis, including systemic lupus erythematosus, an inflammatory, chronic autoimmune disease with multisystemic manifestations, with periods of remission and exacerbation. This study aimed at reporting kinesiotherapy intervention for quality of life, pain and muscle...

  11. Central representation of muscle pain and mechanical hyperesthesia in the orofacial region: a positron emission tomography study

    DEFF Research Database (Denmark)

    Kupers, Rron; Svensson, Peter; Jensen, Troels Staehlin

    2004-01-01

    Functional neuroimaging studies of the human brain have revealed a network of brain regions involved in the processing of nociceptive information. However, little is known of the cerebral processing of pain originating from muscles. The aim of this study was to investigate the cerebral activation...

  12. Evaluation of efficacy and tolerability of eperisone and thiocolchicoside in treatment of low back pain associated with muscle spasm: An open label, prospective, randomized controlled trial

    OpenAIRE

    Syed H. Maaz; Prakash N. Khandelwal; Shiraz M. Baig; Sudhakar M. Doifode; Ulhas M. Ghotkar

    2016-01-01

    Background: Low back pain has a high prevalence in adult population. Because of reflex muscle spasm, muscle relaxants are frequently used either alone or in combination with analgesics. Eperisone inhibits voltage gated sodium channels in brain stem and Thiocolchicoside acts via GABA-mediated mechanism to relax muscle spasm and relieves pain. Methods: This was a prospective; open labeled, randomized, two-arm, parallel group, controlled, clinical trial. 113 patients were randomised to two gr...

  13. Masticatory muscles in the muscular dystrophic mouse. Aspects of the age-related progression of the disease

    DEFF Research Database (Denmark)

    Vilmann, H; Kirkeby, S

    1988-01-01

    Cross-sections of normal and dystrophic digastric and masseter muscles from 7- and 35- to 40-week-old mice were studied in the light microscope. Comparisons of mean cell size, cell size variance and number of centrally positioned nuclei in a given number of fibers were carried out. The masseter m...... muscle seems at both ages to be far more affected by the disease than the digastric muscle. However, the progression of the disease from 7 to 40 weeks is more pronounced in the digastric muscle than in the masseter muscle....

  14. Effect of brief daily resistance training on occupational neck/shoulder muscle activity in office workers with chronic pain

    DEFF Research Database (Denmark)

    Lidegaard, Mark; Jensen, Rene B; Andersen, Christoffer H

    2013-01-01

    PURPOSE: This study investigates the acute and longitudinal effects of resistance training on occupational muscle activity in office workers with chronic pain. METHODS: 30 female office workers with chronic neck and shoulder pain participated for 10 weeks in high-intensity elastic resistance......%, respectively. Compared with control, training increased isometric muscle strength 6% (P relaxation (EMG gaps) decreased acutely in the hours after training. By contrast, at 10-week follow......-up, training increased average duration of EMG gaps by 71%, EMG gap frequency by 296% and percentage time below 0.5%, and 1.0% EMGmax by 578% and 242%, respectively, during the workday in m. splenius. CONCLUSION: While resistance training acutely generates a more tense muscle activity pattern, the longitudinal...

  15. Clinimetric evaluation of methods to measure muscle functioning in patients with non-specific neck pain: a systematic review

    Directory of Open Access Journals (Sweden)

    Smits-Engelsman Bouwien CM

    2008-10-01

    Full Text Available Abstract Background Neck pain is a significant health problem in modern society. There is evidence to suggest that neck muscle strength is reduced in patients with neck pain. This article provides a critical analysis of the research literature on the clinimetric properties of tests to measure neck muscle strength or endurance in patients with non-specific neck pain, which can be used in daily practice. Methods A computerised literature search was performed in the Medline, CINAHL and Embase databases from 1980 to January 2007. Two reviewers independently assessed the clinimetric properties of identified measurement methods, using a checklist of generally accepted criteria for reproducibility (inter- and intra-observer reliability and agreement, construct validity, responsiveness and feasibility. Results The search identified a total of 16 studies. The instruments or tests included were: muscle endurance tests for short neck flexors, craniocervical flexion test with an inflatable pressure biofeedback unit, manual muscle testing of neck musculature, dynamometry and functional lifting tests (the cervical progressive iso-inertial lifting evaluation (PILE test and the timed weighted overhead test. All the articles included report information on the reproducibility of the tests. Acceptable intra- and inter-observer reliability was demonstrated for t enduranctest for short neck flexors and the cervical PILE test. Construct validity and responsiveness have hardly been documented for tests on muscle functioning. Conclusion The endurance test of the short neck flexors and the cervical PILE test can be regarded as appropriate instruments for measuring different aspects of neck muscle function in patients with non-specific neck pain. Common methodological flaws in the studies were their small sample size and an inappropriate description of the study design.

  16. Reduced task-induced variations in the distribution of activity across back muscle regions in individuals with low back pain.

    Science.gov (United States)

    Falla, Deborah; Gizzi, Leonardo; Tschapek, Marika; Erlenwein, Joachim; Petzke, Frank

    2014-05-01

    This study investigated change in the distribution of lumbar erector spinae muscle activity and pressure pain sensitivity across the low back in individuals with low back pain (LBP) and healthy controls. Surface electromyographic (EMG) signals were recorded from multiple locations over the lumbar erector spinae muscle with a 13×5 grid of electrodes from 19 people with chronic nonspecific LBP and 17 control subjects as they performed a repetitive lifting task. The EMG root mean square (RMS) was computed for each location of the grid to form a map of the EMG amplitude distribution. Pressure pain thresholds (PPT) were recorded before and after the lifting task over a similar area of the back. For the control subjects, the EMG RMS progressively increased more in the caudal region of the lumbar erector spinae during the repetitive task, resulting in a shift in the distribution of muscle activity. In contrast, the distribution of muscle activity remained unaltered in the LBP group despite an overall increase in EMG amplitude. PPT was lower in the LBP group after completion of the repetitive task compared to baseline (average across all locations: pre: 268.0±165.9 kPa; post: 242.0±166.7 kPa), whereas no change in PPT over time was observed for the control group (320.1±162.1 kPa; post: 322.0±179.5 kPa). The results demonstrate that LBP alters the normal adaptation of lumbar erector spinae muscle activity to exercise, which occurs in the presence of exercise-induced hyperalgesia. Reduced variability of muscle activity may have important implications for the provocation and recurrence of LBP due to repetitive tasks. Copyright © 2014 International Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.

  17. A COMPARISON OF TOPICAL MENTHOL TO ICE ON PAIN, EVOKED TETANIC AND VOLUNTARY FORCE DURING DELAYED ONSET MUSCLE SORENESS

    Science.gov (United States)

    Johar, Pramod; Grover, Varun; Topp, Robert

    2012-01-01

    Purpose/Background: Pain can adversely affect muscle functioning by inhibiting muscle contractions. Delayed onset muscle soreness was used as a tool to ascertain whether a topical menthol-based analgesic or ice was more effective at reducing pain and permitting greater muscular voluntary and evoked force. Methods: Sixteen subjects were randomized to receive either a topical gel containing 3.5% menthol or topical application of ice to the non-dominant elbow flexors two days following the performance of an exercise designed to induce muscle soreness. Two days later, DOMS discomfort was treated with a menthol based analgesic or ice. Maximum voluntary contractions and evoked tetanic contractions of the non-dominant elbow flexors were measured at baseline prior to inducing muscle soreness (T1), two days following inducing DOMS after 20 (T2), 25 (T3) and 35 (T4) minutes of either menthol gel or ice therapy. Pain perception using a 10-point visual analog scale was also measured at these four data collection points. Treatment analysis included a 2 way repeated measures ANOVA (2 × 4). Results: Delayed onset muscle soreness decreased (p = 0.04) voluntary force 17.1% at T2 with no treatment effect. Tetanic force was 116.9% higher (p<0.05) with the topical analgesic than ice. Pain perception at T2 was significantly (p=0.02) less with the topical analgesic versus ice. Conclusions: Compared to ice, the topical menthol-based analgesic decreased perceived discomfort to a greater extent and permitted greater tetanic forces to be produced. Level of Evidence: Level 2b PMID:22666646

  18. The effect of dry needling on pain, pressure pain threshold and disability in patients with a myofascial trigger point in the upper trapezius muscle.

    Science.gov (United States)

    Ziaeifar, Maryam; Arab, Amir Massoud; Karimi, Noureddin; Nourbakhsh, Mohammad Reza

    2014-04-01

    Dry needling (DN) has been used recently by physical therapists as a therapy of choice for patients with myofascial trigger points (TrP). The purpose of this randomized controlled trial was to investigate the effect of DN in the treatment of TrPs in the upper trapezius (UT) muscle. A sample of convenience of 33 patients with TrP in the UT muscle participated in this study. Patients were randomly assigned to a standard (N = 17) or experimental group (N = 16). The treatment protocol for the standard group consisted of trigger point compression technique (TCT) on MTP, while the patients in the experimental group received DN. Pain intensity and pressure pain thresholds were assessed for both groups before and after the treatment sessions. In addition, the Disability of Arm, Hand, and Shoulder (DASH) was administered. Statistical analysis (paired t-test) revealed a significant improvement in pain, PPT and DASH scores after treatment in the experimental (DN) and standard (TCT) group compared with before treatment (P < 0.05). The ANCOVA revealed significant differences between the DN and TCT groups on the post-measurement VAS score (P = 0.01). There was, however, no significant difference between the two groups on the post-measurement score of the PPT (P = 0.08) and DASH (P = 0.34). DN produces an improvement in pain intensity, PPT and DASH and may be prescribed for subjects with TrP in UT muscles especially when pain relief is the goal of the treatment. Copyright © 2013 Elsevier Ltd. All rights reserved.

  19. Myofascial pain of the jaw muscles: comparison of short-term effectiveness of botulinum toxin injections and fascial manipulation technique.

    Science.gov (United States)

    Guarda-Nardini, Luca; Stecco, Antonio; Stecco, Carla; Masiero, Stefano; Manfredini, Daniele

    2012-04-01

    A randomized controlled trial was performed to compare the short-term effectiveness of botulinum toxin injections and physiatric treatment provided by means of Fascial Manipulation techniques in the management of myofascial pain of jaw muscles. Thirty patients with a Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) diagnosis of myofascial pain were randomized to receive either single-session botulinum toxin injections (Group A) or multiple-session Fascial Manipulation (Group B). Maximum pain levels (VAS ratings) and jaw range of motion in millimeters (maximum mouth opening, protrusion, right and left laterotrusion) were assessed at baseline, at the end of treatment, and at a three-month follow-up. Both treatment protocols provided significant improvement over time for pain symptoms. The two treatments seem to be almost equally effective, Fascial Manipulation being slightly superior to reduce subjective pain perception, and botulinum toxin injections being slightly superior to increase jaw range of motion. Differences between the two treatment protocols as to changes in the outcome parameters at the three-months follow-up were not relevant clinically. Findings from the present investigation are in line with literature data supporting the effectiveness of a wide spectrum of conservative treatment approaches to myofascial pain of the jaw muscles. Future studies on larger samples over a longer follow-up span are needed on the way to identify tailored treatment strategies.

  20. Effects of a Worksite Supervised Adapted Physical Activity Program on Trunk Muscle Endurance, Flexibility, and Pain Sensitivity Among Vineyard Workers.

    Science.gov (United States)

    Balaguier, Romain; Madeleine, Pascal; Rose-Dulcina, Kévin; Vuillerme, Nicolas

    2017-01-01

    In viticulture, the prevalence of low back pain is particularly high among vineyard workers exposed to sustained and awkward postures. One promising setting for low back pain prevention resides in the implementation of workplace physical activity. This nonrandomized pilot study aims at evaluating the effects of a worksite supervised adapted physical activity program among 17 vineyard workers volunteered to enter either an intervention group (n = 10) or a control group (n = 7).The intervention group followed a physical activity program for 8 weeks involving (1) 15 minutes of warm-up every working day and (2) two weekly 1-hour adapted physical activity sessions targeting trunk muscle endurance and flexibility. The control group was advised to continue normal physical activity. Evaluations were carried out at weeks 0, 4, 8, and 12. Physical capacity was assessed using flexibility tests for the trunk, along with trunk muscle flexor and extensor endurance tests. Finally, pain sensitivity was evaluated by assessing pressure pain thresholds over 14 anatomical locations in the low back region. For the intervention group, the endurance of the trunk extensor and flexor significantly increased from baseline to week 8 as well as the pressure pain thresholds. No change was observed for the control group over the same period. These encouraging results in combination with the high adherence rate set interesting foundations for the promotion of worksite supervised adapted physical activity and, most likely, offer a new promising approach to prevent low back pain among vineyard workers.

  1. Quercetin Inhibits Peripheral and Spinal Cord Nociceptive Mechanisms to Reduce Intense Acute Swimming-Induced Muscle Pain in Mice

    Science.gov (United States)

    Borghi, Sergio M.; Pinho-Ribeiro, Felipe A.; Fattori, Victor; Bussmann, Allan J. C.; Vignoli, Josiane A.; Camilios-Neto, Doumit; Casagrande, Rubia; Verri, Waldiceu A.

    2016-01-01

    The present study aimed to evaluate the effects of the flavonoid quercetin (3,3´,4´,5,7-pentahydroxyflavone) in a mice model of intense acute swimming-induced muscle pain, which resembles delayed onset muscle soreness. Quercetin intraperitoneal (i.p.) treatment dose-dependently reduced muscle mechanical hyperalgesia. Quercetin inhibited myeloperoxidase (MPO) and N-acetyl-β-D- glucosaminidase (NAG) activities, cytokine production, oxidative stress, cyclooxygenase-2 (COX-2) and gp91phox mRNA expression and muscle injury (creatinine kinase [CK] blood levels and myoblast determination protein [MyoD] mRNA expression) as well as inhibited NFκB activation and induced Nrf2 and HO-1 mRNA expression in the soleus muscle. Beyond inhibiting those peripheral effects, quercetin also inhibited spinal cord cytokine production, oxidative stress and glial cells activation (glial fibrillary acidic protein [GFAP] and ionized calcium-binding adapter molecule 1 [Iba-1] mRNA expression). Concluding, the present data demonstrate that quercetin is a potential molecule for the treatment of muscle pain conditions related to unaccustomed exercise. PMID:27583449

  2. Changes in electrical pain threshold of fascia and muscle after initial and secondary bouts of elbow flexor eccentric exercise.

    Science.gov (United States)

    Lau, Wing Yin; Blazevich, Anthony J; Newton, Michael J; Wu, Sam Shi Xuan; Nosaka, Kazunori

    2015-05-01

    This study investigated changes in electrical pain threshold (EPT) after repeated eccentric exercise bouts to test the hypothesis that fascia would become more sensitive than muscle when greater delayed onset muscle soreness (DOMS) is induced. Ten young men performed two eccentric exercise bouts (ECC1, ECC2) consisting of ten sets of six maximal isokinetic eccentric contractions of the elbow flexors with the same arm separated by 4 weeks. Maximal voluntary isometric contraction torque, range of motion, muscle soreness assessed by a visual analogue scale (VAS) and pressure pain threshold (PPT) were measured before, immediately after and 1-5 days after exercise. EPT was assessed in the biceps brachii fascia (BBF), biceps brachii muscle, and brachialis fascia (BF) 1 day before, immediately after, and 1, 2 and 4 days after exercise. All measures showed smaller changes (P fascia becomes more sensitive than muscle to electrical stimulation after the initial eccentric exercise, suggesting that damage inflammation to fascia than muscle fibres is more associated with DOMS.

  3. Individuals with chronic low back pain do not modulate the level of transversus abdominis muscle contraction across different postures.

    Science.gov (United States)

    Miura, Takuya; Yamanaka, Masanori; Ukishiro, Kengo; Tohyama, Harukazu; Saito, Hiroshi; Samukawa, Mina; Kobayashi, Takumi; Ino, Takumi; Takeda, Naoki

    2014-12-01

    The aim of this study was to evaluate the thickness of the transversus abdominis (TrA) muscle in three basic postures in subjects with and without chronic low back pain. Subjects were classified into a chronic low back pain group (n = 27) and a healthy control group (n = 23). The thickness of the TrA muscle was measured at rest and during the abdominal drawing-in manoeuvre (ADIM) in supine, sitting and standing postures using B-mode ultrasound imaging. Contraction ratio (TrA thickness during the ADIM/TrA thickness at rest) was calculated for each posture. At rest, the TrA thickness in the sitting and standing postures was significantly greater than in the supine posture (p postures in the low back pain group. TrA thickness was similar in the low back pain and control group in all three postures. During the ADIM, TrA thickness was significantly greater in the control group than in the chronic low back pain group in all three postures. The contraction ratio was also significantly higher in the control group than in the chronic low back pain group in all three postures. These results indicate that the automatic postural contraction of the TrA observed in the control subjects in the sitting and standing postures was not demonstrated in subjects with chronic low back pain. The present study revealed the one aspect of different response of the TrA muscle to changing posture between two groups. Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. Evaluation of the immediate effect of acupuncture on pain, cervical range of motion and electromyographic activity of the upper trapezius muscle in patients with nonspecific neck pain: study protocol for a randomized controlled trial

    OpenAIRE

    2015-01-01

    Background Nonspecific neck pain can cause considerable suffering, possible disability and reductions in quality of life and productivity. The aim of the proposed study is to evaluate the immediate effect of acupuncture on pain, cervical range of motion and electromyographic activity of the upper trapezius muscle in patients with nonspecific neck pain. Methods/Design A total of 12 patients with nonspecific neck pain and 12 healthy subjects will be enrolled in a randomized, single-blind crosso...

  5. Isokinetic imbalance of adductor-abductor hip muscles in professional soccer players with chronic adductor-related groin pain.

    Science.gov (United States)

    Belhaj, K; Meftah, S; Mahir, L; Lmidmani, F; Elfatimi, A

    2016-11-01

    This study aims to compare the isokinetic profile of hip abductor and adductor muscle groups between soccer players suffering from chronic adductor-related groin pain (ARGP), soccer players without ARGP and healthy volunteers from general population. Study included 36 male professional soccer players, who were randomly selected and followed-up over two years. Of the 21 soccer players eligible to participate in the study, 9 players went on to develop chronic ARGP and 12 players did not. Ten healthy male volunteers were randomly selected from the general population as a control group. Comparison between the abductor and adductor muscle peak torques for players with and without chronic ARGP found a statistically significant difference on the dominant and non-dominant sides (p muscle significantly stronger than the adductor muscle. In the group of healthy volunteers, the adductor muscle groups were significantly stronger than the abductor muscle groups on both dominant and non-dominant sides (p muscle strength was also significantly decreased on the affected side. This imbalance appears to be a risk factor for adductor-related groin injury. Therefore, restoring the correct relationship between these two agonist and antagonist hip muscles may be an important preventative measure that should be a primary concern of training and rehabilitation programmes.

  6. Influence of a scheduled-waiting task on EMG reactivity and oral habits among facial pain patients and no-pain controls.

    Science.gov (United States)

    Nicholson, R A; Townsend, D R; Gramling, S E

    2000-12-01

    Recent research has strongly implicated the role of psychological stress in the development of temporomandibular disorders (TMD). It is widely reported that oral habits (e.g., teeth grinding) probably provide a behavioral link between stress and the development of TMD symptomatology. Extrapolation of research in the field of adjunctive behavior to the TMD disorders suggests that oral behaviors may develop conjointly with fixed-time (FT) stimulus presentation. The current experiment extended previous research examining this possibility by assessing the influence of experimental stress on masseter EMG and oral habits among persons who met broadband criteria for TMD and no-pain controls. Oral habit activity was assessed via self-report questionnaire whereas masseter